You still have time to rustle up this lovely crocheted poppy for Remembrance Day.

Using a 4mm hook, make 8 ch and join with a sl st to form a ring.(A magic ring so the hole can close up would be even better, but don't worry about this too much if you are a beginner).
Round 1: Make 3 ch, 15 tr into circle join with a sl st into first ch.
Top piece: 2 ch, 1 tr into the next three tr sts (from previous round) sl st into next tr st.
Fasten off yarn. Weave in ends.
Close up hole as far as you can do (this will be done already if you used a magic ring)
Cut out a leaf shape from a piece of green felt and stitch to back of flower. 
Sew on button over where the hole would have been. (Note:If the whole is still to big, stitch a small round of felt/material on the back that you can then stitch the button securely into)
Add a brooch clasp to the back, or a simple safety pin if you prefer.
Job done!!
* You can choose any colour button, but I have found black or dark colours look more authentic.