For all kicks the higher the knee lift the better. For mae geri remember to drive the arm through first then forward with the hip and leg.
Try to do all kicks without a step forward (less telegraph). Stand taller in the stance makes kicking easier. No step required.
For side kicks throw the knee of the kick directly sideways. I.e. off the front right leg throw the right knee left, lift the knee as high as possible, then rotate but not too far. The foot should finish horizontal (I tend to angle the toes down)
Jumping mae geri. The leg kicking is the leg pushing off the ground. In left foot forward fighting stance push off with the left leg, throw the right knee as high as possible then strike with the left. Remembering to push forward with the hip and tuck the foot under the bum.
Spinning back kick is a great kick in sparring and easier to do than a normal back kick. May need to step across or switch first.
Crescents are also good for knocking down guards or chins.
Roundhouse (Thai) remember to get the knee as high as possible and come in from the side.