One of the biggest difficulties I face as an amateur artist is actually finding time to do the painting. Chatting to a colleague of mine once, who is in the same predicament, she mentioned that it was all about headspace. You might have a gaping three hour gap in your day ahead of you, but that won't necessarily mean that you can fill that time with art.
I have a day job, working in a film makeup shop five days a week, which takes up a lot of my thinking time. Then I also review theatre productions, which can cut a huge chunk out of my evenings too. Finding time to paint is often a problem. Today for instance, I am off work; the sun is shining and my time is pretty much my own. In my head, I should be cycling to Richmond Park to try some plein air painting. But in fact, I have to stay indoors and complete a small commission for somebody who has requested a memory of his time in London.
It's been huge fun to do, but there's a part of me which is nagging to get on with something outdoors. I think time management is one of the most difficult skills an amateur artist has to acquire. I keep trying though.