The above guidelines were written in the context of requesting wallpaper submissions for MX17, but they are applicable in general for all wallpaper contributions.
Besides uploading your contributions to this sub-board, you can also upload your contributions to MX website's Community-submitted Wallpaper pages at https://mxlinux.org/community-submitted-wallpaper
as stated in the wiki link above.
Now that we have more users of MX and the forum community has grown, we welcome more contributions of MX-related wallpaper for the benefit of the community. Currently we have very few creators -- and by "creators" I include artists, graphic artists, people who take photographs, people who manipulate photos, art, drawings and graphics, etc -- taking the time to even post 1 or 2 backgrounds, and I'm sure there must be more of you around with all sorts of different ideas, styles and abilities.
If you are a creator/modder of icons and themes, you are also very welcome to submit your contributions in the MX Art sub-forum. The wiki link's notes on licences and copyright will be applicable to icons and themes as well.
The best images may find their way into a future release of MX Linux as part of the official default wallpapers. Even if a wallpaper is not included in an MX release, other forum members can still enjoy your contributions and download them for their own use.
Please refer to the wiki link in the first post for details on:
a) recommended picture size and ratio* of wallpapers (ignore file size max limits if you aren't uploading to MX Community itself)
b) MX logos and resources that you might wish to use with your backgrounds
c) licences and copyright
Expanding on the wiki note on licences and copyright, if you are using/manipulating other people's photos and images as part of your own artwork, please use base material to which you have all necessary permissions, or that is public domain or has acceptable licence terms as set out in the Wiki post. You don't have to for the purposes of merely posting your own desktop screenshots. However, your artwork can't be uploaded to the MX Community Wallpaper pages nor selected for official MX use.
Even with the small restrictions above, there is a lot of scope for creativity and a broad range of resources that can be used. So please go ahead and amaze us with your ideas!
* It was a choice between 16x9 and 16x10 screen ratio. We are recommending the latter for now because there is still older hardware (e.g. some netbooks) with that screen ratio even if most new displays are now 16x9. But if your preference is to create 16x9 wallpapers in 1920x1080 resolution or higher, please don't let that stop you. :-)