Those are the simple instructions for making a mum boutonniere. You can substitute daisies if you wish. Other flowers, such as roses or carnations, are simply wired a little differently, but the other steps are basically the same.
Don't forget the important step of sealing your corsages and boutonnieres. Since these flower designs don't have a constant water source, hydrating and sealing the petals is an important step in keeping the flowers fresh throughout your wedding day.
Refrigerate if possible and don't put them in the back. Household rRefrigerators are sometimes colder in the back than the front and can freeze flowers if you aren't careful.