1. Tell your friend to block his inventory space (so there's no free 2x2 slot space in his inventory in this example)
2. Drag any item from inventory to your hands (for example protector case)
3. Stand in front of your friend
4. Now, start bandaging yourself from inventory (or drinking, or eating, etc)
5. While doing action, the item from your hands will go back to inventory, now drag this item on ground
6. Your friend MUST take item you dropped to his/her hands and logout while your bandaging animation is still going
7. You logout after him
8. Login again and you both have protector cases