- Know your rivals. Trying to make a Battlefield-esque game? Don't; you won't be able to compete and nobody is going to buy something that just reinvents the wheel.
- Experiment. The more you experiment, the more fun you can make your game. Make the bullets bounce off the walls! Include laser pointers! Be creative.
- Don't make something popular; make something out-of-the-ordinary that will catch the eye of the public. Make something that a critic would want to review.
- Have a good business plan. Critics like TotalBiscuit go deep into this and explore what you're going to do with your game in the future so you want to make something that is going to make you money but has a good quality rating.
- Make a dynamic game. Make it so that people can have fun. Then, people will make "Let's Plays" of your game because each one will be different!
- Have fun yourself when creating the game. Not having fun? The game isn't fun.
- Make something you enjoy playing, so that you can play it yourself. There is also a higher chance of having a larger community if you do so.
- Take time, put effort and work hard on your game. Not got enough free time? Recruit a team member!
- Get crowd-funded. It's a sneaky source of advertising!
There may be a few more that I haven't included so feel free to suggest any below, if they're good then I'll edit them into the post.