ScottTargetTestPrep 's article is really very detailed! That's one of the articles I referred to when I was figuring out how to structure my own routine.
My work situation is similar to yours, so let me share what works for me.
I wake up at 6 am, make coffee and try to rub the sleep away from my eyes. I start studying at 6:30 am and study till 9 am.
I wasn't a morning person earlier, but this has been my routine ever since I started preparing seriously for the GMAT. Waking up early helps because I don't have any work related thoughts to distract me. Also, since my morning hours are the most productive, it makes sense to dedicate them to GMAT prep. My evening hours are less productive since I'm usually exhausted after work.
I have also observed something that might seem counter-intuitive.
I'm more productive on work-days than on weekends.This sounds crazy, doesn't it?
On a weekday, I know that I have to start working from 9:15 am. That hard-deadline pushes me to wake up at 6 am and study.
On holidays, I find myself procrastinating.
I login to work at 9:15 am.
Since I'm working from home now, if I have some free time, I'll study for a couple of hours in the afternoon as well.
Usually, I log off at 6:30 pm. If I'm not too exhausted, I try to study in the evening as well.
I also ensure that I have some planned down-time. Maybe I'll watch YouTube, or watch an episode on Amazon Prime. This helps avoid burn-out.
Since you have scheduled your GMAT in a month's time, it might make sense to go all-out and cut down on all non-essential activities. See what works for you and adjust your schedule accordingly.
TLDR; 1) Try to spend your most productive hours studying.
2) Study whenever you have time. Prioritize tasks that you must do & eliminate the rest.
3) Give yourself a couple of hours everyday to relax so you don't burn out.