By Sane <email@example.com>
Someone gave me the suggestion to write an article like this, and some of this may not be new to you, and I might have stolen stuff from others without thinking about it, but still it should be a help for some of you :)
Some of this is written for RPGs, but most could be applied to other types of games too.
Add secrets, mini games, extra NPCs and stuff to your game, it will make it feel more complete and real.
In the real world you don't usually only see the people that you have to see, or at least it isn't like that in my life :)
Of course, to make your game fun, you should use humor a lot. If you're too boring, you should find someone to help you with writing a story and such :) However, you shouldn't use humor when it doesn't fit. For example, if one of the players allies dies in a RPG, it isn't a very good time to use humor...
Always make the game start out resonably easy, and make it harder as the player goes on. Spend much (or enough) time balancing the difficulty so that it doesn't get too easy/too hard for where the player is supposed to be at the specific point in the game. This applies to puzzles, fights, anything.
You should never make a game that's big just cause you want it to be big. When you run out of inspiration, don't just throw stuff together to make the game big, instead try to put the ideas you've got so far to make it finish at an earlier stage of the game, or let the project rest until the inspiration comes back.
This is probably the most important part of how to make a game that's fun to play. If you don't like to play the game you've created, then who will? Only put stuff into the game that would make you like it more, and others will probably like it too.
This was all I came up with, I hope you like it. Please send any comments to firstname.lastname@example.org.