Just use the first five troops in your barracks
Barbs, arch, gobs, giants, wb. No need to use other troop since they take a lot of time to train. And minions will require DE which is relatively scarce at TH7.
Play with your own ratio. Experiment.
More barbs/arch = faster training time and better for collector raids.
More giants = higher army survivability but lower DPS.
More wb and gobs = better for targeted storage raiding, especially DE storage.
For example, I used:
60 archers
10-12 wallbreakers
8-12 giants
28-40 goblins
Rest barbs (24-40)
Hope it helps. :)