Trying to put a stripe decal over the boot, roof, any tips I'm getting air bubbles

I haven't put decals on a car before, but I have put a protective film over a bicycle frame, which is far from flat.

For that, the method I used was to get a spray bottle that provides a fine mist and put a couple of drops (no more..) of washing up liquid in with approx 500ml of water. Coating both the frame and the sticky side of the film, I then applied the film and, with a fine coat of water between the two surfaces (surface tension of which is broken by the washing up liquid) I was able to move the film around until in the right place. Then finally, I used a small squeegy to encourage the inevitable air bubbles to the edges and left to dry out.

I don't see why this wouldn't work with what you are trying.. good luck!

Do it as Sheylings has suggested. I used to work in motorsport and we had to change decals every race meeting. Squeezy bottle method everytime. Dont be afraid to put too much on as well. It all comes out when you get your squeegy on it

Without a doubt the most frustrating job I ever did on my old car.

I got bubbles even with the spray bottle. However it did allow me to align the stripes as I wanted. After getting as much out with the squeegee as possible, I got a tiny pin and pricked what bubbles remained, then squeezed air / water out of that hole. Not ideal but actually worked well and the hole wasn't visible later.

Thanks for replies, I did as said with good results, only problem I had was with bonnet centre stripe as lots of contours. In the end I put it to one side on the front. I think it looks ok I'll post some photos. If I decide to go centre I'll get a pro to do it.