sorry for the late reply , Stock up on wards dude. as for me i buy 3-4 sentries at the start and place them only on spots that i usually see the invi hero. if the invi hero stays on the lane its safe to put one where creeps are usually meeting up. common mistakes of support players are spamming sentries. just put them on common places u think the invi hero is staying :)
RE: Dota 2 Rotation Guide and Routes for Support Players