Photobucket is your easiest way to upload photos.
Below is a step to step guide.
Click on the button.
This will open up a box where you can find the pictures on your computer you want to upload. You can select more than one picture in a folder by clicking them individually while keeping the 'Ctrl' key held down.
Once you've selected all the files you want click 'Open' and you should see your files being uploaded. Once they're done you'll be presented with something along the lines of the pic below. I only uploaded one pic in this example so you may have more than one depending on what you uploaded.
If you want to you can now add a Title and Description to all your pics then select 'Save and Continue'. Otherwise click on the 'Skip this step now' link.
You should now be in your main PhotoBucket folder with all the pictures you've uploaded. Most recent first.
To now use a picture you've uploaded on the forums you just need to select the IMG Code link below the picture you want to use. Click in the IMG Code box for the picture then click the right mouse button and select Copy (Or Ctrl and C on the keyboard).
Then go to the forum post, click where you want your photo in your post then right click your mouse and select Paste ( or Ctrl and V on the keyboard).
You should see a link appear in your post. To check its worked before posting you can always use the Preview option and see what it looks like. If you don't use the IMG links your picture won't appear correctly on the forum.
^This is not my guide but a simple to understand one that i found online^
Hopefully this has been a simple enough guide for everyone to follow.