To solve a 3x3, you need to understand move notation. Once you have learnt, it's time for step 1!
The goal of the first step is to make a white plus.
(If you hear about a 'white cross' they are the same thing.)
This step is mostly intuitive and it shouldn't take long for you to work out the tricks ;)
The second step is to solve the first 2 layers,
frequently called "f2l".
Follow the flow chart and pick the right tutorial.
1. Bring the corner and edge to the top layer.
2. Put the corner over its corresponding slot.
3. Do a U move.
4. Are the top colours matching?
Yes - Do an F' and then move the edge behind where the corner was, then do the alg: F U2 F' U F.
No - Do the 'yes' option, then do the alg: R U R' U2 R U2 R' U F' U' F.
1. Bring the corner and edge to the top layer.
2. Put the corner over its corresponding slot.
3. Do a U move.
4. Are the top colours matching?
Yes -