@nprofile1q... You can totally do an underdrawing before putting the oils on, I know people say you're not supposed to use graphite but I've used hard pencils (3H-4H) in the past and just draw very lightly and I've never had any problems with it being visible on the paint. People online also recommend using charcoal but I personally haven't tried it, it feels to me like it'd muddy up lighter pigments