Do you need a mesh? If you are recolouring a hair, clothing, or accessory, downloaders may need a custom mesh for your content to work right. If you don't know whether a custom mesh is required, it's very easy to check: cut and paste the contents of your Downloads folder somewhere else temporarily. Then put in only your creation, and load the game or Body Shop. If it shows up correctly, you don't need a custom mesh. If it doesn't show up correctly and shows a Maxis default instead, you do need a custom mesh, and you'll need to figure out what one it is. This can be tricky if you have a lot of meshes - best way is to make sure you know what mesh you're recolouring before you ever start!
Including Meshes: If your creation does require a custom mesh, you may wish to include it in your upload so that downloaders can just get what you've uploaded and not have to go anywhere else.
Once you've identified what mesh it is, you need to check back with the original creator on their site or forum and see what they say about that - look for a FAQ or policies page to see what they have to say about including their meshes. They may not want you to include their mesh, or they may only be okay with it if you include their readme file as well.
Please do not include meshes that are uploaded on MTS, even if the creator says it's okay - this creates redundant uploads.
Do not include meshes that the creator says not to include, or if the creator doesn't say. If you get special permission to include a mesh that normally cannot be included (or the creator's policies don't say anything) please say in the text of your upload post that you have permission - we can't read your mind!
If you do include the mesh, make sure you include a credit and link in the text of your post - and make sure you state that the mesh is included! Also, please do not include the creator's "template recolour" file - you only need your recolour and the actual mesh itself.
Linking to Meshes: If you cannot include a mesh, or the mesh is hosted on MTS, link to the mesh in the appropriate spot when uploading - when you mark your upload as a New Mesh Recolour you will get a screen asking you to link to the mesh. Please give as direct a link as possible - to the page where the mesh is, if you can. If you cannot give a direct link, or if there are a lot of meshes on the page, please give directions in the text of your post, as clear as possible... i.e. "Look under Female, Adult, Everyday, then go to Page 4, and download the black dress with the blue belt outfit - the mesh is included with it." Please do not hotlink the mesh - i.e. you want to link to the page it can be downloaded from, not the actual rar or zip file with the mesh in it - hotlinking is bad manners.