It is completely trial, error, and maintenance. It's like writing a computer program without really understanding the programming language. And then you finally get something to work, but later on "bugs" will be revealed and you'll have to fix them.
For me, lamictal has been great, and I'm BP I. My pdoc is adding depakote to the mix because he thinks I'm on the brink of hypomania. Boo hoo!
Now after about 10 days on the depakote and reduction in lamictal, I'm feeling tired and a bit down. IMO depakote doesn't stabilize, it just completely prevents manic symptoms. At best, you'll be flat with depakote. Sounds fun, eh?