What you need:
Post it notes
I also used a large 'd' flashcard for the purpose of copying and prompting.
This was a really simple to do activity, Elsie had post it notes and a pen and we searched the house for 'd' items, every time she found one she attempted to write a 'd' and stuck her post it note on it!
It was actually quite hard to find thing that began with D but she really enjoyed it and it held her attention for a good 30 minutes (maybe longer.) It was also a good way to encourage letter formation and mark making.