First, and most importantly, know what genres of photography you enjoy the most and if that genre requires a tripod. Then, buy the largest, highest quality tripod you're willing to carry that fits in your budget. Specifically in that order; do not put budget ahead of any other aspect of the tripod. If you go too cheap, you may very well end up with a tripod that meets none of your needs when you're forced to replace it due to instability or fragility. The adage, "buy cheap, buy twice (or more)" applies here.