In a conversation I had the other night with one of my students, we discussed the value of establishing the context in which a magical act will occur, as well as how to establish that context. I find that without proper context, magic ends up being meaningless or reactionary, and consequently isn't as effective as it would be if the person took time to establish context properly. Proper context establishes why a person needs to utilize magic, as well as how it'll be utilized. One of the activities I have my students when they first start learning magic involves putting together a diagram or flowchart for something they want to do magic for. I have them map out what they are already doing on the mundane level to achieve their goal and then we look at where magic fits into that process, and how they will use magic to help them enhance what they are already doing. The value of having a person diagram their process is that it shows the person that magic never occurs in a vacuum, but instead always has a context it occurs in, and part of that context is framed in the activities the person is already doing to realize the possibility they are trying to bring into reality.
Of course context isn't just your mundane activities, but also your goals, the other people affected by the working and other environmental factors which need to be thought about, if we are to use magic strategically. Strategic use of magic allows for the different factors and environmental conditions and enables you to successfully enchant because you've accounted for them and prepped the conditions accordingly.
So, as an exercise map out what you want to accomplish and include what you are already doing, and then add magic as a supplementary activity that enhances what you are already doing. Your success rate will more than likely go up because you'll have considered all the factors involved.