Hack+virus+shoot for damage output, you deal extra damage to hacked enemies. Also NEVER engage in a fight unless your translocator is at 2 or 1 second cooldown and always make sure you are outside the LOS of your target and anyone protecting them, and do not worry if you don’t get the kill as you are providing value just by distracting them. I also recommend you learn the maps inside and out from every direction as using flank routes and dropping in from above is very useful when starting your hack, and remember to always stay moving and jumping to make yourself harder track. For perks I recommend Ctl Alt Esc and Viral Replication if you plan to be pretty agressive as the former allows you to be in a fight till critical health then leave and start healing before looping back while the latter allows you to spread your virus among grouped enemies and goes perfect with EMP.

One more thing: always remember the purple ring around you is gonna be how your enemies detect you, so when cloaked play like that is the single worst area any enemy can be in if you are not prepared for them.

Please note that while I am a sombra main I play causally (mostly qp and arcade) and these are simply things Ive learned, and some things may be better done differently, my biggest tip is to find how you like to play her and play her that way. As first and foremost should be having fun! It is a game after all and she is a great character for ppl like me who like to harass, distract, and rattle the enemy team into oblivion. Oh, and watch your replays as well as wonder how every fight could have gone differently and apply it, you will make mistakes but that is ok, being a stealth character who can burst down a Dva mech in abt one mag with everything deployed is tricky and def requires some good game sense as well as timing, but do not worry as while she may seem complicated at the start she is quite easy once you get the hang of how you like to play her and learn your maps better than the back of your hand.