Step #1: mix a 1:10 mixture of dish soap in the proper sized flat tray.
Step #2: Make sure the water is Room Temperature.
Step #3: Pour some of the mixture into a spray bottle and spary area where decal will go.
Step #4: Soak Water Slide Decal until you feel a slimy feel between decal and backing paper.
Step #5: Slide decal to edge of backing, place backing at starting point of rocket.
Step #6: Slice decal onto rocket, hold with opposite hand finger, and slowly pull backing paper from under decal while rotating rocket (if on air frame) until backing paper is clear.
Step #7: Lightly use finger tips (or flat object) to position the decal.
Step #8: After letting is sit for a few minutes, use a flexible flat edge to squeegee out the excess water into a tissue or paper towel.
Step #9: Let set for 24 hours or, apply heat with a blow dryer or heat gun set a low heat and use a sweeping motion to set decal.
Optinal; Step #10: Use flexible 2 part epoxy (fishing rod building epoxy, and any additives like pearl or color) and cover the entire rocket and let set for 48 hours
The epoxy not only gives it a durable finish and shine, but will put a "defense shield" bonded totally around the rocket exterior and guard against decal damage.
If you think rockets are bad, try putting a Pheonix Bird on the hood of a shaker hood of the Trans Am!!!! Now that is some sq. footage at one time! And get it on sqare!!!!