If you want use ← ↑ ↓ → and Ctrl as FIRE choose Kempston Joystick.
Keyboard: Forward = O, Back = K, Left = Q, Right = W, Rest = R, Step Size = S, Angle = A, U Turn = U, Gun = SPACE, Fire = 0, Up = P, Down = L, Face Forward = F, Stand or Crouch = H, Interrupt Game = I