If you are planning corsages and boutonnieres for a wedding, the ladies in the bridal party can have fun making them a day or two before the event.
While most people get whoever is handling their flower arrangements to tackle this task too, it is actually much cheaper to make them yourself.
My friend saved about $200 dollars doing this as a fun craft project with her bridesmaids. We had a bit of an afternoon get together, had lunch and by the time we were finished, we had lovely accessories.
Everything you need is available at the craft store. We bought silk flowers (you can use real ones too), some flower tape, a bit of wire, ribbon and corsage pins.
Basically you just arrange the flowers the way you want, secure them with wire and use flower tape to give it a clean look. The pins are used to either secure the arrangement to a lapel, or ribbon for your wrist.
There are lots of step-by-step videos online for more details. It is very easy to do.