I'd say, treat it like a lump of clay. Got a couple story arcs we could go in? cool, toss it in. Know 'kinda where you want to go with some personality types? awesome. push it all together. Now, which do you feel like working on today and build that up a little. A painter would then think, which parts need the most attention? work on that a little. 

I think there is not a hard-fast check list to follow or an ordering that is important here, gradual build up comes from different places. Here is an example of what came to me today. The following are two of my characters that I've been refining from some time. The winged creature is also my art and was built for something else as a larger beast. Turn that around and make it a gecko++ sized shoulder pet for the female with large enough wings to drape over her shoulders, that would be a pretty cool combination. And now her personality has been altered to something much more dramatic. so, as you work it's also cool when those happy accidents or turn of events put it all together. No need to set everything in stone right from the get go.

Start with a clump and polish it into something shiny.

Thank you for your time.

Would you like to share some of your idea? The [ Blogs ] here on the site are good for that. Check it out.

On 3/12/2019 at 10:31 AM, Carlos Daniel Lopez Romero said:

well im starting to learn stuff to make a 2d platformer but basically my question is that im deciding on making characters building the game itself writing the story, so how you usually create your characters their personalities and the story overall like for example you write first the story and then the characters or backwards and also i would appreciate art tips. 

thank you to you all.

hmmm....what I did was start making the game I wanted to make, and then developed things like story and characters...not because I had a real story to tell, but only to give the graphic design some sort of a direction. For example: if my games story was about ancient magic, I'd design tiles and backgrounds for castles and forests and have enemies like knights and wizards. If my games story was sci-fi, I'd design stuff around apocalyptic wastelands, starships and have enemies like robots and aliens.

My game is a simplish 2D platform shooter and didnt require a very detailed backstory, so I just kept the story simple. But if your game is a complex fantasy RPG you might need to pay more attention to the story and characters.

7 hours ago, Carlos Daniel Lopez Romero said:

thank you to you all i think i kinda get it like i have to build the game and according the type of game i want i need to create the characters and story and stuff

yep. Story writing can be a neverending process. Its better you just start making your game and then develop story ideas around the game. Its much easier and it also gets things done!