Please note that the Third Street is very important in the course of the Seven Card Stud Poker game. At this point all the big decisions are made which would subsequently result in a profitable or unprofitable ending.
Before making any major decision try to figure out what cards are already out, how many players are after the pot when your turn to bet comes, how many players are left in the game and how significantly the pot has been raised in the meantime. Once you have done a quick analysis of the situation you are good to continue. The advisable hands at this stage would be those that play well in multi-way pots, for instance drawing hands (three-flushes, three-straights). As to the big pairs, they definitely work better in shorthanded pots.
The Third Street strategy imposes selectiveness, especially with starting hands. Any mistake during this round can lead to undesirable consequences in the long run. Try to notice the cards that are out in order to perceive the best moment to throw away your best hand.