Help keeping herbs alive?

I try every year to grow herbs, very unsuccessfully. I've just bought my first rosemary bush, a couple of basil and an oregano plant. How can I keep them alive? I don't know what I do wrong but I usually lose my basil within weeks. I keep the soil moist, not wet, it's in indirect sun for about 4 hours a day. My rosemary usually ends up drying up and dying when I transplant it to a larger pot even though I water it and try to keep it from drying. I give it as much direct sun as possible. This is my first experience with oregano.