You have to get away from the mindset of always wanting to do things in the most efficient way possible because you otherwise think you "wasted" your time. Just do the things you like the most. If that means having 10 hours of fun with things you like instead of having no fun with doing maybe 3 hours of things you don't like but just do because it's more efficient, so be it. Having fun is more valuable than having no fun. At the end you will be finished anyway and don't know what to do then.