There is no answer to this question that is correct for everyone in every circumstance. It depends upon the "things" involved, how strongly the subconscious mind is attached to them, what is going on in your life at the time, and how you respond to hypnotic suggestion in general. The safest strategy for beginners is to start with just one project – perhaps an easier one – then, with some success and experience under your belt, progress to other, more difficult objectives.