Russ
lets start with the assumption you have the picture loaded to a site- such as 
photobucket and you are using a windows machine (i don't know about macs)
three ways to do it, in each case-  open the picture in 
photobucket (or where ever)
first way
right click the mouse (or mouse pad on a laptop) on the picture and one of the options will be copy image location
left click on that
what you saved looks like (with out the dashs)
 -http://i248.photobucket.com/albums/gg195/setterw/image_zpsdcaxdyda.jpg-
you can click on the image tab above-  the yellow postcard thing with mountains (sorta) and erase what is in there and paste this address in there and hit enter
==================================================  ===========================================
OR
second way - right click and copy (same as above) 
then
you can paste it into your post and put a   [IMG] in front of it and a [/IMG] at the end
so bracket-IMG-bracket-http://i248.photobucket.com/albums/gg195/setterw/image_zpsdcaxdyda.jpg-bracket-slash-IMG-bracket
will give you  
==================================================  ===========================================
or - in 
photobucket  when you have the picture open you will see links on the right -   one is labled "IMG" 
click on that - it will turn yellow and say copied-  then you can paste that into your post