The community needs to develop an active test project; it must remain active until approval (automated statistics, recent changes). It is generally considered active if the analysis lists at least three active, not-grayed-out editors listed in the sections for the previous few months.
"Wikipedia talk" (the discussion namespace of the project namespace)
Files should be uploaded to Commons, but if you want, you can enable local file uploading.
Notes: (1) files on Commons can be used on all wikis; (2) this setting can be changed afterwards; (3) uploading fair-use images is not allowed on Commons (more info); (4) localisation to your language may be insufficient on Commons