Using a large home made sgueegee to mask larger decals. The sgueegie was constructed from a scrap piece of Optix .22" clear acrylic. A 18"x24" sheet of Optix can be purchased from Lowes for $20 and will make you four sgueegies. I then purchased a long strip of adhesive backed Velcro and used the felt side (soft side) to wrap around and apply to the edge of the sgueegie.
The sgueegie covers a huge area and is perfect for both masking (application tape) and applying larger decals to your substrate. This is an affordable method that has saved me some time and virtually eliminated any mistakes (air bubbles, etc.) and I thought I would share it.
If you have any questions or suggestions please share them. Thank you!