Whether you're a clerk or a CEO, the time to leave will arrive. Often that's not easy, practically or psychologically.
The Big Picture Ideas
First of all, try to ensure you'll be moving to something better: a better job, a rewarding retirement, etc. That will make it easier to be your best self in recruiting and grooming your replacement.
But even if you're about to be dumped without a good future in the offing, remember that an important part of your legacy is often to find and mentor someone even better than you are, at least better for your workplace's next few years. So beware of the human tendency to pick someone inferior so you look better in comparison. The mature person realizes that such sabotage hurts not only the organization and deprives a more qualified person of the position, but also cheapens you.
After selecting your replacement, try to be the wisest, kindest mentor you can be. That means, yes, sharing what you've learned on the job and what you think is most needed moving forward, but also recognizing that you're not trying to create a clone of yourself. Your successor will bring his or her own talents, desires, and limitations. Part of your job is to facilitate that person's being their best self.
A Step-by-Step Plan
That's the macro advice. Here is a step-by-step model for preparing to pass the baton. Of course, you may need to modify this plan to suit your circumstances.
1. Form a small selection committee. For example, your boss, a key coworker(s), and key customer. In developing your successor's job description, rather than listing what you've done, have it reflect what's most needed during the next few years.
Danger: Committees tend to stuff the job description with too many requirements. Pare down to what's really important. That will help you screen applicants based on what’s central. That also avoids your creating a job description so intimidating that even good candidates are deterred from applying.
2. Using that job description as a screening tool, consider your employees both one and two layers beneath you. Sometimes, a rising star could be the wisest choice even if that person isn't "next in line."
3. The selection process should contain simulations of tough tasks required on the job. Don't place much stock in candidates' answers to interview questions. Even if you ask uncoachable questions, the interview is a poor predictor of job performance.
4. When you've selected your replacement, if possible, make it a tentative selection. Start the grooming process and if things aren't working out well, either of you can back out before the deal is finalized.
5. Individualize the grooming process. That can consist of some combination of their job shadowing you, you observing the person, inviting him or her to increasingly take your responsibilities, having weekly mentoring meetings, and inviting ongoing questions.
6. After the person replaces you, decide if it's wise to stay on the job for a few months or even a year after passing the baton. If so, make the case to your boss, if you have one.
7. Leave feeling you've left a worthy legacy. Now you can move on—perhaps with help from colleagues and friends—to figuring out how to make the next phase of your life your best yet.
If You Want Someone to Take Over the Business You Own
1. Try to dispassionately weigh the pros and cons of leaving it to a family member. You don't have to hurt your business just because you care about your child. If s/he isn't the right person to run your business, ultimately you do a disservice both to your child and to the business you worked so hard to create.
2. Think twice before selling your business to someone you think is likely to cheapen the product and/or provide worse service just to make a few extra bucks. You're selling your legacy. Treat it like the treasure it is.
Marty Nemko's bio is in Wikipedia.