One of my ADHD hacks is to single-task to a degree that a neurotypical would probably not benefit from overall. Too many tasks to do? Overwhelmed by trying to remember them all and tempted to nope out entirely because my working memory can't hold that much information? Well, clear it out, now there's only one thing on my to-do list today. It doesn't matter what it is as long as it's something I need to do reasonably soon and it doesn't depend on something else being done first. If it does, it gets deleted and replaced by the something-else that needs done first.
This results in finishing errands and other tasks in a weird and not well-prioritized order, but they are getting finished. Usually when one is done I'll either pick a different thing or stop for a little while and pick a different thing later; even if this doesn't occur, at least I did one thing instead of zero.
