If you don't already have an account on
photobucket.com or similar type site, you should start there.
Once your account is established you can start uploading pictures from your computer. If the pictures are on your smartphone, simply email them to your account.
Once the photo are uploaded I click on the picture and it will have several links to the picture. Right click the one labeled img, then select all, then copy, and finally paste to your post.
These instructions are from memory and not me doing it as I type this. Please forgive me if I posted incorrect information, it was not done on purpose. If that doesn't work, pm me and I will try and help further. It seems harder than it really is.