Need advice from Step Fathers/Fathers please

Well I did not see one thing on here and I will give you this. Avoiding saying NO in the first place with him. Avoid making something a command when a request or an option will work. See if you say you must get down and walk on your own then you are stuck with enforcing your command so he understands boundaries. So only make it a command when you have to. He will learn the difference. He doesn't like NO from you because you are new and different and he enjoys you.
So make sure you are not going off in the other direction just to show him who is boss or to set boundaries. Say no when it has to be no, yes when it can be yes, then share the rest of the times with them. Life is too precious to spend it making rules and saying no.