I know I've mentioned this before, but it bears repeating. Not all pagans follow the Wiccan rede. Nor is the belief in the Threefold Law/Karma universal. I do not follow the rede, and I do not believe in karma or the Threefold Law as many people do.
So what do I value? Personal responsibility is very high up there on the list. What this means to me is really considering what consequences - good or bad - my actions will have. Consequences can come back in many ways. Sometimes they're physical, sometimes emotional, other times they are spiritual. Sometimes the consequences affect us, sometimes someone close to us, sometimes an innocent person we don't know.
So before doing something, I must stop to consider the possible consequences of my actions. Who will I affect, and how? It's not always an easy thing to do. There can be a number of outcomes for any given scenario, and it can be hard to account for the free will of others. This is why when doing spellwork, we must be very clear, specific, and focused - no matter what the goal is. Even then sometimes there will be unseen consequences. When we mess up, we have to be the ones to step up and clean up our own messes. No one else should have to do it for us. (However, that doesn't mean we can't seek help if we truly find ourselves in over our heads - or help others who need it.)
It is also important to "know thyself." No one can really know your motives except for you, to know if we are doing something for the right reason. Really examining ourselves is not always easy, but it must be done.