For future reference Phil, log into the SW site as normal.
Choose 'My journey' on the left hand side, then 'view my progress'. From here you can add in your start date, start weight, goal weight, and each weekly weight too. So far as I know this is fully backdateable too, so you can add them now.
Once all that is up to date, you can choose 'my awards', which is still under the 'my journey' tab, and view your awards all together.
**** Select the one you want, right-click it and choose 'copy image location', then come into minimins, go to user CP then edit signature, choose the location in your signature where you want it to be, and click on the 'add image' button (hover over the buttons one by one, it will tell you what they are). A box will come up asking for location, just right click in the box, and choose 'paste'. ~~~~
Repeat from **** to ~~~~ for each image you want to add into your signature.
Good luck