I'll try Jim, 

First, have you created yourself an OFC Album yet?

If not, look at the top blue menu bar, right-hand side, between Calendars and Control Panel, click on Albums.  Within that resulting screen, on the upper right-hand side, find the Actions window and click Create and edit your photo albums.  

After you create your Album you'll be able to upload (properly sized and formatted) pics there.

After uploading you'll need to copy the photo's URL address (location). It's what you'll paste into the Insert/Edit Image dialog window when you're composing your post. The Insert/Edit Image icon is the 5th icon in the icon bar within the post composition area.

Hope that helps.  Sorry, I couldn't make it any less cryptic.