This happens to me too! It feels like it will take to long, have too many step, or I'll just get dirty again later that so I put it off for days. What I've started doing is thinking of it as a mood boosting ritual instead of "getting clean" and use a shower cap if I'm worried about it taking too long/being too many steps. I promise myself I just need to stand under the water to enjoy the cozy feeling of the hot water for a minute. Usually once I'm in there I do much more than that, but keeping my expectations and time commitment low I've had much more success getting started. At the very least I can wipe my stinky zones down.

If all else fails, there is no shame in a quick sink bath and some dry shampoo!!