Son pees all over the toilet seat

My son is almost 4 and sits to pee. He has absolutely no control standing and pee ends up all over the toilet, walls and floor. Sitting is slightly better. But when he sits he still owes all over the seat and it goes between the toilet and the seat and ends up running down the toilet and on the floor. How do I make sure he gets 'it' in the toilet so the pee does t squirt through?