This is a guide that is hopefully useful. I am not in the higher leagues, however in standard play this build is fun, and deadly. This guide is not to be used as strict law for the build order and abilities, rather this guide is supposed to help the reader progress and understand the great character Tristana.

AD carry Tristana is a fun character to play. Especially as a starter, the auto attack offer a great stepping stool to other characters without as much micro. Tristana isn't only for beginners. Tristana allows for a great early push and for late game domination. Tristana has some great tools up her sleeve. Rocket Jump for instance allows for a quick escape with an AOE landing, great for either offensive or defensive maneuvering.

Has good early game push
If fed then snowballs rapidly
Can carry the team
Can clear lane quickly just with getting the last shot
Can steamroll whole teams if used properly

Squishy character
If left alone can become very vulnerable
Tends to be weak around the mid game(if not fed well)