Tests for OH- Ion.
The Hydroxide Ion
Add universal indicator paper, it should turn blue.
Or add red litmus paper which will turn blue.
Or add to a substance with an ammonium ion, and ammonia will be produced.
Test for CO3 Ion
The Carbonate Ion
Add Hydrochloric acid (HCl) and bubble the gas into limewater, should turn it cloudy.
Test for SO4 Ion
The Sulphate Ion (1)
Add a little hydrochloric acid and barium chloride and there will be a white precipitate.
Test for SO3 Ion
The Sulphate Ion (2)
Add hydrochloric acid (HCl) and there will be bubbles of a choking gas produced.
For identifying halogen ions (like chlorides, bromides etc) add a small amount of nitric acid (HNO3) and a small amount of silver nitrate (AgNO3) and look at the precipitate.
Cl- There will be a white precipitate.
Br- There will be a creamy coloured precipitate.
I- There will be a yellow precipitate.
The halide precipitates get DARKER as you go down the group.