You can upload the pictures onto a website like
www.tinypic.com or
www.photobucket.com & use the direct links. Simply right click & press copy or ctrl+c! I'll use tinypic as an example.

"Browse" and click on the file you want to use. Then press "Upload".

Then use the "direct link for layouts", right click & press "copy".
THEN...
When you make a post, there is a tiny button that looks like this:

Click that, & (img)(/img) will probably pop up on your text box (except with brackets, not parentheses). Simply press ctrl+v or right click & press 'paste'.
You can do this numerous times with numerous pictures! It's best to press enter twice after each one so they're more spread out.

You then press "preview" at the bottom if you want to make sure you did it correctly, or "post" to just post it! Hope I helped!