Dosage, dosage, dosage! Observe the effects, and work with your prescriber to find the dose that's best for you (assuming this is the right drug for you, which of course may not be the case). Through quite a bit of trial and error, I arrived at a dose of about 60 mg a day, which I manage by taking 50 mg (half a 100 mg tablet) 4 days a week and 75 mg (the smallest tab available) 3 days a week. I'm generally sensitive to medications, and many people tolerate and benefit from much more, but the same principle applies: weigh the cost and benefits and see if you can optimize their balance through adjusting dosage (always in consultation with your prescriber).
Specific side-effects
hypomania
Sleeplessness
Burden
I have to be conscious of dosage day to day, and occasionally still get blood pounding in my ears on the higher-dose days - haven't really checked to see if this is related to actual higher blood pressure or is just a kind of hypersensitivity. It's a little unpredictable, and can be unsettling when I'm trying to sleep, but seems to be diminishing over time.