At the Hack-Space last week there was a "Instamorph" night. We decided to make a phone holder.
What you need:
1x Bag of Instamorph
Step 1: Melt
So get your Instamorph, it usually is in tiny rice like granules, and put them in boiling water.
Once they have melted go to the next step.
Step 2: Stretch
Take the Instamorph out of the boiling water and stretch it like so. You need it to be double the length of your phone.
Step 3: Morph
Now mould the Instamorph round your phone, like this.
You need 2 of these.
Step 4: Put Them Together
While the Instamorph is still malleable, push them both together to form a case-type holder for your phone.