editing size

I'm trying to get my shoes to fit. If I use edit & 'stretch' there appears a number of white squares that I can drag to stretch the shoe, What is the difference between all the squares, they seem to do the same thing ?

The item will expand in the direction of the white handle that you select, unless you have the "Streach both sides" option checked. For expanding a prim shoe, it is advisable to check that option, as it keeps the shoe centered on the ankle side-to-side. This requires less adjusting after expansion, to position the resized shoe correctly.

Welcome. I hate Prim shoes, very few places that sell or give shoes look right on the
feet or they look like clown shoes.
When object is joined the x, y, z axis looks like squares.
If object is modifiable you could click edit tab this other section called
edit object with stretch selected.
Make sure the little boxes are checked then select the individual parts of the shoe
to change size.
Problem with shoes that are made out of prims sadly is they never seem to fit
my feet to look right, when adjusting the prims if you are allowed too prims don't
allign the way you want them to when you're new and inexperienced adjusting prims.
It takes bit of practice.
It is like be whole lot easier to just build your own shoe on pose stand but then
shoe tend to stick through the ground that why I personally avoid prim shoes
and use textures.
It is all very confusing at first to figure out different things, I still get confused and I have
around for a while.
If you need a snapshot of edit tab and other areas around the object tab, explanations let me know and I post a pictorial guide to show you and anyone else who might need it .
Have fun, I am off to bed.

http://www.howcast.com/videos/59016-What-Is-a-Prim-Second-Life-Video-TuTORial-QUICKTIP
Check this out there might be some information in how to edit a joined prim too.
I didn't get chance to look at whole video.

Also look at Edit Linked Parts. If yo ucan do this, you can move the individual parts of the shoe....

But be careful, it is easy to ruin them

Shoes are a pain to edit...and some are No Mod, so you can't edit them at all.

Instead, edit your feet. Almost all womens shoes in SL are created to fit a Size 0 foot. So open Appearance mode, and shrink those tootsies!

But...you really SHOULD learn how to edit objects, including multi-prim objects. Go to the Ivory Tower Library of Primitives and walk through their hands-on tutorials. They will answer all your questions and then some.

Torley Linden tutorial videos I think are the best.
The very basic guide here to how to edit attachments.
Although I wish it was more in depth.
http://www.howcast.com/videos/59248-Editing-Attachments-Second-Life-Video-TuTORial-QUICKTIP
I personally found Prim tower of primitives bit confusing.