i went for months like that, just sleeping about 12- 15 hours a day, spending almost all my time in room when i was awake. what helped me was to like exposure said, set an alarm everyday and even if you don't wake up at that time, or you turn it off, keep setting it everyday. like i started trying to just wake up before noon, somedays i would be like screw it, and sleep past 4pm, and others i could wake up around 1 pm, and i was slowly able to start waking up earlier and earlier. and i tried to do something positive each day, like maybe a chore around the house or look online at jobs, or read part of a self-help book. because some, well a lot, of those days i would do nothing productive at all, and it helped me atleast being able to say to myself, well at least today i put away the dishes, thats more than i've been able to do on some days.
and sometimes you have to give yourself a break, and if you did have to do something stressful the day previous (like interacting with people), sometimes you may want to just sit the next couple hours out. but you have to give yourself a timeline, and not give yourself permission to sit the next week out because you had stress.
sometimes just getting yourself in a sitting upright position, or getting your feet to touch the floor, and staying in that posture until you feel more awake can help.
i think it starts with goals, and accepting that small steps are ok- and it's a process- and it took me months to get out of, but i just tried to keep in mind that facing forward is where i want to be.
lol i like your advice ignace!