Easy support build...
First put some wards on the map to get safe and then start farming (Last Hit) to get Arcane Boots.
Then the game can start for you : Use Smoke of Deceit with your team and start making some kills to take the advantge.
Don't forgt to push a lot with this hero because you have crazy damage with your passive so you can kill ennemi tower easily.
If you get some gold buy some aura stuff (Vladimir's Offering) because you and your team will need them (don't forget you're playing support).