Here is what you need:
...and a little bit of ...
Hot Glue.
Start by cutting the fake flower off the long stem.
Add a little glue to the end of the stem to secure the head of the flower on.
(Since I got my flowers at The Dollar Store, the blooms popped off pretty easily.)
Use a little bit of hot glue to secure the stem of the flower to top of the pen.
Get your floral tape ready...
Wrap the floral tape around the pen, from the top to the bottom.
Stretch the tape as you wrap to make it sticky.
When you get to the bottom of the pen, double back on the wrapping a little so the end of the tap is not right at the bottom.
I put them in a vase to display them for the shower...
And then each guest got to take one home with them as a little gift.
Another idea would be to put them in a flower pot and give a set of them as a gift...
perhaps for Mother's Day!