Self-adhesive Vinyl Border - application advice please

[Nightsky]

I haven't used a self-adhesive vinyl border before and wonder if anyone has any advice to complete a neat job.

I do seem to remember comments about it not sticking properly to the surface - this is going over vinyl wallpaper and painted wall to finish job.

 

[Nightsky]

Well - it's on. I was surprised at the ability to peel off and replace but my nerves are shattered.