Instructions:

1. Cut a paper plate in half.  Decorate using felt tip pens.
2. Cut a handle out of black card and stick it to the paper plate using masking tape.
3. Cut several lengths of wool / glitter strips and attach these to the the back of umbrella.
4. Add some beads / gems etc. for raindrops, or some cotton wool for snow.

All items (or similar) are available from Play Resource Shop & Scrapstore.