The 2 biggest things I changed in my painting habits to preserve my brushes for longer...
1. Don't let paint get up around the ferrule (the metal collar) of any brush you care about. Only wet the bottom most portion of the brush, if you let the brush get wet further up, paint will work its way into the ferrule and destroy the brush. This does mean I stopped using my good brushes for mixing and thinning paint, now I use an old crappy brush to get the paint out of the pots, mix it and thin it, then swap to my good brush for the actual painting part.
2. Use soap regularly. I will admit I don't even use brush soap

I've just been using a cheap bar of hand soap (don't use the liquid stuff, it doesn't work nearly as well). Wash the brush off in water then gently run the brush over the bar of soap, just gently work it in with your fingers and then rinse the brush off in water again. You can keep repeating until the brush is good and proper clean.
While painting, I'll rinse the brush in water every couple of minutes just to make sure paint isn't drying in it and then occasionally (maybe every 10 minutes or so? I don't actually time it) wash it out with the soap to get it properly cleaned up. My main brush I've been using for a year and a half and it's only the past couple of months it's started to degrade a bit to the point where I'm thinking of replacing it.
If you've got paint dried in a brush, I imagine a dedicated brush cleaner would work better, but I just make sure I don't let paint dry in it by washing regularly during painting.
But definitely it's most important to not let paint get anywhere near the ferrule, if it does wash it IMMEDIATELY with soap and water and pray that you got it all out.
Smacks wrote:The forked bristles usually happens because people twist the bristles when they reform the brush tip. A lot of people do this, and I've even seen it advocated in painting tutorials, but it's a bad habit, because it trains the hairs to point in different directions. When you reform the tip you should try to stroke them straight down.
I haven't heard of that one. I don't swirl my brushes anyway but still a good thing to keep in mind.