Started a new project i need advice ( i will not promote)

Hi, i started a project which i will officially launch near Q3 this year. So i wonder should i open a company and fill for a trademark, or wait until project gets users and some activity then begin with legal stuff. Project will be free initially, and then at some point of time i will add some paid features, this could go even to next year this time. Please advice me, what would you do ?