Keep in touch
When you are on a long leave you must keep in touch with your colleagues. Your happy return will depend on how you behave during your leave. Keep your skills up to date by taking up a freelance project. You can spend your long vacation meaningfully by joining a professional organization or go for occasional get-togethers with coworkers. You can have a network or very well be in a book club of your former colleagues.
Play your cards carefully
Your personal needs and situation may change when you go on leave to have a baby, or to take care of a sick relative, or to rejuvenate yourself. At the end of the day, you may not be able to work full time. Don't hesitate to tell your boss facts, but choose your words carefully. If you tell him that your first priority is your children, you may be waving a red flag in front of the bull.
Show what you have done
It is not worthwhile to measure the hours you have put in. But measuring what you have accomplished is more meaningful and paying. The best way to please your boss is to make him know what and how you are doing. List out your projects, with their status and the steps being taken and to be taken and present it to your boss. Don't take chances to allow your effort to go unnoticed. Better prepare a one-page summary to show that you are delivering the goods. It makes a hell of a lot of difference.
Clear choice
Don't just jump back into the fire. If you do so, the purpose of taking leave is defeated. Be sure you are returning to work to enjoy. If not, change the job or the career. What you perhaps want is to find a company whose values are similar to yours. If effect, you don't want to go back to a job that is as miserable as the one you had left.
If you think your company doesn't fit your changed lifestyle, say good-bye to it. Don't think it is impossible. You can negotiate a job that suits you and your time. You can even clinch flextime or part-time arrangements. Don't try to adjust yourself to your new job. Like in life, you have to make many adjustments in professional career as well. Solving the work-life dilemma once doesn't mean that is the end in itself. It is like a journey; perhaps you have to change the route several times to reach the goal. So take it in its stride.