I studied for a BSc in Psychology between 2011 and 2015 while also working full time and, for the first 2 years, being a single parent. It's all about working in 'slots' and utilising what is usually empty time such as lunch-breaks, waiting at the doctors, and school pick-up as well the obvious times of evenings and weekends. Try to maintain a constant rather than do nothing for a couple of weeks and then be swamped!
Joh, OU graduate