The task of rereading your journals is best left to when you have some free time available. You don't want to be pressed to get them read between lunch and dinner if you're the cook, chief bottler-washer and have to get the kids bathed and to bed afterwards, too. Holidays are a great time for committing to rereading your journals. You should be able to really sink down into them, not be worried about what time dinner is on and have no plans to go out that night, either. The time you'll need to reread is another good reason not to let too many journals gather dust before you've gone through them looking for your gems.
If you suspect some of the material you'll read will dredge up unpleasant memories, emotions or leave you feeling too fragile, organise to have a support person to turn to later. You could ask a friend to call you on the phone that evening, watch a movie with a friend or partner, or just do something with another human being. Even if you know you're safe and nothing much happened over that period, it's still sensible to arrange someone to touch base with. You may feel overly vulnerable after going through some thoughts and issues you've otherwise forgotten about. Just seeing your real self on the page could also leave you with a sense of hopelessness, even mild depression.
In A Writer's Book of Days Judy Reeves suggests you arm yourself with highlighter pens and sticky notes for a rereading session of your old notebooks. I'd add a small notepad and/or your current journal, also. You certainly want to catch any ideas you have while rereading. Revisiting your journals is an experience you'll want to record in your current journal, too.
Select different colour highlighter pens for different the different areas you've covered in your journals. You might like to use pink for references to events as they happened, such as birthday celebrations, trips taken, your baby's first step and major world events. Perhaps green for the areas of real growth and progress; yellow for emotionally charged entries; blue for story ideas; and orange for poetry or personal essays. You get the picture. Just decide before you start and stick with it so you can easily locate the pieces again. You might like to use the sticky notes to flag the pages you decide need working into something more than a simple journal entry.
Expect to be delighted by yourself, to see spelling errors galore, to yawn over some of your more tiresome entries and to learn a lot more about yourself than you ever expected. Some issues will have been resolved and you'll feel tempted to glance over them. Try your best not to. Read again how you felt when you didn't know what you understand now. Take it to heart that you will also be able to come through next time you face a major issue or similar problem in your life. And look for patterns or issues that continually crop up again and again.
Certain themes begin to suggest themselves as you read your entries. These may be easily seen, but be prepared to dig deeper if such patterns aren't obvious to you at first. Take the opportunity to indulge in a few days of thought on this. These patterns and routes of your life may need some time to develop. Writing about it in your journal will help this process, too.
I hope these ideas help you when you embark on the journey of rereading your journals. Please share on this topic in the comments section below.