So many wedding venues these days only allow real petal confetti, and this can be very expensive. If you have the time, drying your own rose petals is a much more economical way of recycling any bunches you may recieve, and using those you may have in the garden yourself. I personally do not have the space to air dry rose petals, and if you are not doing this regularly, buy extra equipment, like silica gel or drying racks, is a pain.
If I am drying a small batch of roses, I simply use a microwave, paper towel and a dinner plate. Depending on your microwave, you'll need to test how long you put the rose petals in there for (mine is 750w and 1 minute 15 seconds does the trick). Lay out a piece of kitchen paper on your dinner plate, place the petals on the paper towel, try to not overlap them too much but if they're touching I don't find it matters. I usually get almost a whole rose on one plate. Pop in the microwave for your alloted time and voila! Dried rose petals! I did this for my own wedding - I use to buy bunches of about 10-12 small roses from Lidl or Aldi for just £3 each week, enjoyed them in a vase then dried them when they were going over. They still smell good too!
If you're using these for confetti, think about making your own paper cones to give out to guests. I used an old botanical book I found in a charity shop and virtually followed the same instructions for making a piping bag except I added a staple for more stability.
p.s. when I made enough petals for 50 guests to have a small paper cone each, so about a handful. This worked out at about 1.5 roses per person + a few extra for good measure!