First of all, Stop, dont main sombra she is purely situational.
If you didn’t listen to the first requirement then I will pass a long some useful information.
Hack health packs on your side and the enemy side above all
Hack high priority targets, for example healers/DPS or tanks that rely on ability’s.
Make sure you watch translocater carefully and dont be afraid to TP out early.
Practice your aim a lot because you need constant head-shots to pick off healers and low health targets.