If you’re overwhelmed seek comfort in the fact that if you do something then you have taken a step forward. Start with small reasonable things that take ten minutes. They give you the energy and motivation to do the big things. Eventually this builds into self control and organisation which allows you to do the huge things.
When you get demotivated and start procrastinating look back at what you did to remind yourself what you can do.
Oh and write lists. Lists are cool. Don’t procrastinate by spending ten hours reading HN trying to find some list software though; just use whatever you have on your phone already (I just use reminders on iOS). Don’t use some outliner software on a PC because you need that on you all day every day.