oh boy an opportunity for my nitpicking and snobbery. *hand rubbing intensifies*
- a short blurb at the beginning really helps. this is not the time to write an essay about your games development and inspiration, talk about yourself, or drop the whole story, but to let me know what kind of game it is and it's purpose. you can do all of that still, ofc, but let me know what i'm looking at first.
- make your first screenshot your best screenshot. at the very least make it an actual screenshot of your game in it's current state. also, after about the third-ish screenshot down i really appreciate when you start putting them under spoilers in small groups.
- similar issue with videos. i really, really do not need a conga line of eight videos each at 30s long demonstrating one specific feature. nor do i need eight 2hr videos about the game's development. that can all go in the thread, of course, but it really doesn't need to be smack dab in the middle of the thread where i'm still learning about the game.
- no links beyond the download link (if any). it's ok for extra material, but i am not going elsewhere to watch your trailers, see your screens, and so on.
- be sensationalist within reason. yes, you want us to try/buy your game but there is no need for giant banners, gaudy colors, and so on like you're a used car salesman having a big summer blowout. keep your showcasing simple and complementary to your game.
- when building your "advertising" stuff like trailers, keep in mind that in this case i'm already on the thread. i know your game exists, what i don't know is why i should care.
- make the title helpful or thoughtful. things like "my game" or "random game" tell me nothing except that it's a game. chances are, i already knew.
- excitement, depth, and personality are fine but sometimes you may want to consider making lengthy stories and things that are only tangentially related to your game as posts in the thread rather than parts of the OP.
- if you offer a demo, make it a little more than a title screen and basic functionality. it's pretty boring to just move an unfinished character around an unfinished room and have literally no other interactions whatsoever.
- links to your other projects should really go at the end.
- if you use spoilers, give them a descriptive title so i can differentiate between them as well as easily be able to find content i'm looking for.
that's all i can think of. take from it what you will.