Start a file somewhere. Use whatever is familiar and comfortable for you. Make it something easy with a very low barrier to usage. You might even just start wit

Start a file somewhere. Use whatever is familiar and comfortable for you. Make it something easy with a very low barrier to usage. You might even just start with an email draft. Put a link to this discussion in it. Over time, cull through this discussion and create a To Do list. That To Do list might include things like "validate the idea." If you need a team, make it a goal to create a team. Research how other people have done that under similar circumstances. Do things like collect links to "founder dating" type sites. You might also look for info on single founders. I have some info on single founders curated on an old blog of mine and can give you the link if you want to look through that. You might try getting a copy of the book Wishcraft. It has very pragmatic information about how to get stuff done in spite of being busy and all the usual human excuses for never getting anywhere. Start working on the project, even if all you do is write a short overview or intro to a design doc. But you need files and some means to organize them and keep them all together so you can gradually build on these small crumbs of things. I haven't looked at it in a long time, but I used to read through the YC application and I wrote up some of the answers for me personally as an exercise. If you can get a copy of their current application, start a file and start making notes concerning how you would answer parts of it. If you can't answer some things, make notes about what you need to do to get to the point where you can answer it. Best of luck.