1 - Have a dedicated space. There is nothing like a space that says "now I am going to work" to prompt action.
2 - Avoid distraction. For me, that would be news sites or stock markets. For some people, it might be TV or FaceBook or other things. You know what your weaknesses are - avoid them.
3 - I know your manager will be stressed. Worried the work is not getting done. Put him or her at ease with a couple of video calls (works way better than just a phone call) and a daily report. The format I like for a daily report "my goals today were...I accomplished...things you should know....my goals tomorrow are....and things I need from you".
4 - Avoid temptation. If you have unhealthy food in stock, you will likely eat it. Only stock the healthy stuff.
5 - Plan. I know I work better in the office OR at home if I have a plan. One trick I do is say "what are the top 3 things I will have done today". Invariably I get them done - just because of this planning.
6 - Much of my success can be attributed to habits. Good work at home is about having good habits.
7 - One of the first things I would do is study it. Google. Search Youtube. There is a ton written on this.
A PC Magazine article on it here.
And more (not in my words)