Respect any boundaries
If your partner is insecure, it’s likely that he/she has some boundaries. Maybe the whole “lights-on” thing is out the window, or maybe showering together is off-limits for now. Whatever the boundary may be, be sure to respect it, at least early on in the relationship. Once you two get more comfortable with each other, you may want to get a bit daring and push those boundaries. That way they don’t become overbearing or troublesome.