I made a map (minecraft bow one) and I wanted to post it to the internet. How would I do this?
First, plug an USB storage medium into the PS3. Start up the PS3 and log into the account. In the menu, navigate to Game ▶ Saved Data Utility (PS3™). You will see a long list of savegames. When highlighting the savegame, It says 'Minecraft: PlayStation®3 Edition' and in smaller text under it the world name. Highlight the desired savegame and press △ (Triangle Button) ▶ Copy ▶ USB Device. Wait until the progress bar fills up and shut down the PS3. Remove the USB storage medium from the PS3 and plug it into a PC. Press (Windows key) ❖ + e to open the file explorer. Click on the USB storage medium ▶ PS3 ▶ SAVEDATA. The folder you see there is your world.
For online distribution, it's recommended to put this folder into a ZIP file. Windows has built in methods for working with ZIP files. Right click on the world folder ▶ Send to ▶ Compressed (zipped) folder. You will see a new file with the extension .zip, give it a recognizable name. Now, you will have to upload it to an online storage medium. Popular online storage mediums are Mega, MediaFire, Dropbox and Google Drive. They will give you a link that you can share to online social media such as Reddit and Planet Minecraft.
Try going to a forum and introduce it. Make sure to take a picture of it and post the image in the website. Sites such as Minecraft Forums and Reddit are useful. You may also make a video of this. If it's about a server, best you tell them it's a server. If it's a world seed, make sure to post the seed.