Complex sentence: Outside darts he makes and tests slings for chemical offshore companies as he is only a part time darts player, he has expressed his desire to go full time on the circuit which joining the pdc will let him do.
Split into simpler sentences: Outside darts he makes and tests slings for chemical offshore companies as he is only a part time darts player. He has expressed his desire to go full time on the circuit, which joining the pdc will let him do.