lemmingllama authors an incredibly helpful Meta Analysis For Early/Mid/Endgame. This will help you decide on the best damage & gold sources no matter what stage you are at! Currently up to date for version 5.19, it can be found here!

Once you have decided on a build, it will be time to set your Skill Tree and familiarize yourself with how to play your new build:

Clan Ship

Dagger

Gold Gun

Heavenly Strike

Pet

Shadow Clone