Welcome to the Nintendo Database Forum Fan Art/Fic Board. Here you can post all of your Nintendo-themed art, be it drawings, models, stories...
But there are certain things you must take into account:
1. FIND HOSTING You will need somewhere for your art to be hosted, so you can link to it from here. In the case of stories you may want to just write straight into the forum, or you may want to link to your own site to do with it. Nintendo Database does not (currently) host fanworks.
2. NO FANGAMES You know what these are... stupid post-inflating topics where each member posts a single word/sentence response until some kind of story takes shape... or some kind of all-encompassing battle saga where people undoubtedly get into arguments. These topics will be deleted, and you will lose all your posts. I will also turn off post-count in this forum if it becomes a problem.
3. NOTHING OFFENSIVE You'd think drawing Nintendo characters would be as harmless as pink fluff... but you never know. I'm a tolerant guy, but I trust you to use your judgement.
4. BE ORIGINAL It's all very well you loving someone else's story or artwork, but don't claim their story or pic to be yours when it isn't. Try to draw your own pics where you can, rather than clipping official art or sprites. Remember that there's loads and loads of Nintendo games out there - not just Mario, Zelda and Pokemon.