The best tip I can give you is start and don't stop. I'm one of those people that easily falls prey to not finishing stuff if I stop. (Which is what happened to my own fangame… At least it wasn't released at any point.)
- Work on the most story essential stuff (as far as you have a story) first and finish it. Padding can be added later.
- Add your own flavour to your fangame. Even if you don't stray from the standard formula of exploration and getting effects, it's still a good idea to add something that makes you game identifiable among the crowd. E.g.: .flow is recognizable by its gritty, industrial style with body horror as a common motif, Ultra Violet has a lot of pastel colours and bunny-themed things, stuff like that.
- This is more of a personal preference, but avoid adding a hell maze. These worlds are commonly hated among fans, lack creativity and they often don't add anything to your game other than frustration. Smaller mazes are fine, though.
Some tips for pixelart:
- Practice small pixelart and go from small to bigger. Bigger pieces tend to take more time and patience. Find a scale you are comfortable with.
- Avoid using 100% black and 100% white, especially together. (Same goes for any highly saturated colours, like the ones commonly associated with MsPaint). It really strains the human eye to look at such intense colours. If you look at e.g. the White Desert in Yume Nikki and compare that to 100% black and 100% white, you'll see that the White Desert uses less intense colours. It's fine to use these for e.g. sketches and temporary lines, but in finalized pieces they should be nowhere to be found.
- Avoid pillow shading at all costs. (This one counts for art in general.)
- Try thinking of each tile in RPG Maker as roughly a 1x1m or 3x3ft square. You don't have to take scale too seriously, though, especially if you stylize rather than go with realism.
For music (finding music - I can't make music myself):
- I tend to prefer Japanese resource sites as they usually aren't very strict with any non-commercial use of their stuff. Try looking for loop sections as these are in general more fit for games. Do take note that some songs end with fading out music rather than cutting off to start again if you use MP3/OGG music rather than MIDI, so always check how it ends. Post too long. Click here to view the full text.