If your splitboard is new you shouldn't need to adjust your tip, tail or split clips. All clips should slide smoothly and the board should feel securely locked together when the clips are closed.
If your splitboard is used and the split clips (ie the clips between bindings and tip/tail) are not pulling the board halves tightly together, you can adjust the clip tension. To adjust, loosen one half of the clip and spread the halves further apart. Tip and tail clips should require no maintenance unless clip is damaged or broken.