This tutorial should help you to upload your images from your machine to the OSW gallery so you can share them in your threads.
I've noticed today that it works really smooth, probably all due to RoninSix' efforts.
Guidelines, before you begin:
JPEG format is generally recommended unless you're doing something fancy like a PNG with clear background.
It 'should' be less than 1000x1000 pixels, this will depend on your image dimensions so it may come out to 800x600 which is pretty decent and will avoid the following yellow 'image has been resized' bars.
Images larger than this will not upload.
In turn the file size will be under 200kb and everything will load faster.
Step 1. Go to the Gallery
Step 2. Go to Upload
Step 3. Click 'Browse' and select your image from your computer.
Step 4. Fill in the Title and Description for your image. It can be the same.
Then for Category, choose Main Album unless you prefer another.
Step 4.5. If you had uploaded more than one image you will see this Processing screen.
Check if everything looks ok and click 'Process' towards the bottom.
If you upload only one image then you will skip Step 4.5
Step 5! You can view your uploaded image in your album.
To post the image that you've uploaded, copy everything in the 'Direct Link Code' box
Step 6! And paste it into the text box.
Then you will have to add the IMG /IMG tags. They should be in the   brackets with no spaces.
Hope this has helped you. Please feel free to add to it or offer suggestions to make it better. Good luck!