Work both sides. The common adage is that Moms may make the rules, but Dads enforce them. Dad are tough, moms are soft. Children need both nurturance and structure - the support and the stern - but it's easy for parents to wind up splitting the jobs, rather than both doing both.
Don't. If you're always and only the drill sergeant, your sons wind up seeing you as only that - tough, rigid, intimidating. While in your own mind you're doing what you're doing because you care and are worried, what they see is a guy who is always on their back, always nitpicking, always on edge.
It's this impression that will be imprinted on them, and which they are likely to pass along to their own sons. Give your sons more than a one-dimensional view of you and fatherhood. Do it all - nurture and be tough when you need to - and help your partner to do the same.
Understand your own father to better understand yourself. Just as you want your sons to see the complexity that is you, it's helpful for you to move beyond the one-dimensional view of your father that you probably walked out of your childhood with. Updating your view of him can help you change your view of yourself, and reduce your fear of making his mistakes. So go beyond How's work, how's the car, how's the weather talk, and ask your father about his past struggles, present fears, his life-long passions to shake up your old assumptions and discover what made him tick.
And if he has moved out of your life, or passed away, spend some time doing some reflecting. Help recover and heal your past by writing him a letter saying whatever you wished to say before he died but couldn't, and then write a letter back from him to you saying what you wish he would have said. Though emotionally challenging, this process can help heal old wounds, and allow you to move on to be a father of your own making.
Help your son understand the man cave. As Men Are From Mars, Women Are From Venus has pointed out to now generations of newly married couples, men and women tend approach problems differently. Women process and ultimately make sense of emotions and problems by talking them through. Men go into their cave and, well, mull, for what can seem like a long time. They work out the problem in their heads and eventually come out an issue the punchline - I want to do this, we need to do that - often skipping the back-story, much to the frustration of their partners.
If you tend to be this type of guy, be sensitive to the fact that your son may not understand what you are doing. He can take your mulling and withdrawal personally, misinterpret your behavior as somehow tied to him, or cause him to be worried about you. If you need to withdrawn, let him (and the rest of your family) know what is going on - that I'm okay and it's not about you, I just need to sort some things out and think about them by myself.
Teach your son how to do. My grown son was with me at the hospital when my father was on life-support. My stepmother was understandably over-wrought about what to do next. I was able to calm her down, and stepped up and made a clear decision based on what I felt my father would have wanted. A few weeks later my son called me to say how much he valued being there with me, and seeing how I sensitively but clearly handled the situation. He felt it was a good model for him on how to do the same.
He had an opportunity to learn a lesson perhaps about managing one of life's transitions, but these opportunities and lessons are always there. There is a Buddhist saying - How you do anything is how you do everything - and successfully navigating through life is about the how of what you do rather than the what. This is what you want to teach your son. Help him understand how you think, how you tackle problems, life's stresses and strains - how you react when someone cuts you off in traffic, when someone gives you the wrong change at a store, when you feel frustrated with a job or task and don't know what to do next.
Teach him how to stand up and be assertive about things that he feels are important, about how to recover when you've been discouraged or defeated, or how to take action and solve a problem when you feel emotionally overwhelmed. Tell him stories about times when you struggled, when you had doubts, when you did something courageous. Help him learn how to steer the boat that is his life by letting him see how you steer yours.
Give time. It's really the only thing that you truly can control and give. Money can always be lost, but time is lost only if you let it. It's not the quantity that's important but the quality - it needs to be dedicated solely to him. Stanley Greenspan, the famous child psychiatrist and pediatrician, urged parents to do what he called "Floor Time:" Dedicate a certain amount of time everyday - half hour, hour, 15 minutes - for 1:1 time with your son and let him decide what you will both do together. You may play a video-game together, you might wrestle, watch TV, read a book, bake a cake. It doesn't matter. He gets your undivided attention, he gets, for a change, to be in control, and you get to discover the inner life of your son. Do this everyday, don't ever cancel it as punishment. It's for him, unconditionally. You'll be surprised at the difference it can make in him and you.
Build up the positives. Sure, you have standards that you want your son to reach, but he'll only get there if you can encourage him with plenty of praise and positives. Let him know how proud you are of him - not for scoring the goal in the game - but for who he is. Counteract your own father, perhaps, and focus on what he did well on his report card first, then talk about problems. Anytime he shows the seeds of being a good man - is considerate, is responsible, is proactive, is compassionate - let him know. Without your feedback his efforts are likely to sink under the radar and be lost.
Teach guy stuff. In the era of Goggle and Youtube, you can learn practically anything on your own. But real important learning comes from what is passed down from father to son. You're his entrée to the man world. Teach your son about your passions -- cars, clothes, the zone defense. Show him how to tie a tie, educate him about relationships with women, help him understand the focus and value of work. Not everything you say will stick - he may have no interest in cars, soccer not basketball may be his thing - but that's not the point. The point is the relationship, taking the time and responsibility for shaping him. You have the opportunity to be his greatest teacher. Don't blow the chance to be one.
Apologize. This is something some men don't do very well - they can be arrogant, they blame others for their problems and emotions. They see apologizes as caving in, you win, I lose.
Telling your son that you are sorry you over-reacted, that you didn't mean to hurt his feelings, that you made a mistake goes a long way in not only repairing the relationship, but in teaching him an invaluable lesson about responsibility and humility. You're teaching him that it's important to be aware of your impact on others, and when it's hurtful, not what you intended, you step up and say so. Apologize to make it right.
Love your partner. Certainly a strong relationship with your partner provides a solid foundation for your son's development, but what he needs to see most is how you get there and keep it up. You are the model, often the only model, for showing your son how intimate relationships work - the handling of differences, showing affection and respect, managing your own emotions. You don't need to be perfect, but you need to be proactive. You don't always need to be calm, but you do need to be clear and sensitive. Skip the speeches or lectures. Instead just focus on everyday-integrity - do what you say and believe.
If any of this seems a bit overwhelming, don't worry, you have plenty of time and plenty of room for making mistakes. Kids are forgiving. If you're not sure how you're doing as dad, simply step back and take stock: Can your son come to you with his problems? Can he share his emotions? Can he respect your advice? If he can, you're on solid ground.
And if you both are struggling - if he is pulling away, dismisses what you say, is afraid to come close - it's up to you to change the dance, to break the pattern. Approach, even if he initially pulls back. Talk, even if he is at first silent. Spend time, give positives. Don't worry about doing it Right, focus on doing it different. Don't under-estimate your influence, your impact.
After-all, you're his Dad.