Oil line fittings should be dry when tightened. I know that doesn't always happen, but at least wipe them off if you spill. Oil lines should be in fire sleeve. Secure the fire sleeve with a Band-It clamp (#1 choice) or an Oetiker clamp. Do not wrench down too much with Band-It clamps with fuel or oil fire sleeve because you can tighten them so tight they will pinch off the underlying hose. You can use fuel injection screw type band clamps on oil lines. If you need to buy oil line the Rotax distributors have it, but they all have something different, but it all works.
No one should be using the screw type wormdrive clamp with the open serations that you buy in the hardware store for fuel or oil.