The only other things I would add that have't been said yet, are: don't buy cheap brushes. Don't use your brushes to mix your paint prior to brushing. Treat the brush carefully when brushing - don't use it like a straw to get paint onto your figure or model. When cleaning, don't push on the bristles too vigorously, do not twirl the brush or push it down to the bottom of the jar of whatever the appropriate cleaner is for the medium you are using. Also, do not twirl it in paper when drying it off. If you look at it, and it looks clean? Clean it one more time. This is the advice the art store gave me.
If you have plastic protective sleeves for the tips, make sure to put them back on to protect the point. If you have lost the point, leave it moist and repoint the tip when putting it back in the sleeve.
Although it's only been about 4 or 5 months, my skills painting figures suck BUT ... I haven't lost a point yet on my good brushes
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You can also get conditioners from real art stores but I haven't needed to go that route yet. I use princeton and w&n brushes. Hope that helps.
GR8Voyager