First things first, talk to your significant other about this. You will end up spending weekday evenings and weekends dedicated to a side project. If you are able to get support at home, then make sure you make the best use of your time (as I am sure you will). The trick is to figure out what milestones you want to hit in the beginning of each week, estimate the amount of time it will take, and spread out the work to each day of the week. Use a calendar or scheduler of some sort because it will keep you on track!