I am literally in your position. I try to put in an hour of studying after work and sometimes an hour in the mornings/on the way to work. I study more on the weekend. Trust me, it is extremely hard but this exam is brutal and you just have to consistently put in time into it even if it is at least 30 minutes a day. Concerning motivation, remind yourself why you want to do this. Let your reason(s) be a motivation to drill/study the concepts. Most importantly, take breaks. Like I am trying to stay away from all LSAT materials like once/twice a week.