Installing large decals or vinyl wraps requires careful technique to ensure a smooth, bubble-free finish. Here are some techniques that can help remove all air and air bubbles from underneath the film:

1. **Preparation**: Ensure the surface is clean, dry, and free of any contaminants. Use a mild cleaner and alcohol to remove any dirt, grease, or wax. A clean surface allows the vinyl to adhere properly and reduces the chances of trapping air bubbles.

2. **Use a Squeegee**: A squeegee is a crucial tool for applying vinyl wraps. It helps in applying even pressure across the vinyl, pushing out air bubbles as you go. Use firm, overlapping strokes from the center outwards to ensure any trapped air is worked towards the edges of the vinyl.

3. **Heat Gun or Hair Dryer**: Applying gentle heat helps soften the vinyl, making it more pliable and easier to stretch and manipulate. This can be particularly helpful around curves and edges. Heat also helps to eliminate wrinkles and air bubbles. However, be cautious not to overheat the vinyl to prevent damage.

4. **Application Technique**: Start by peeling off a small section of the backing paper and apply the exposed area. Gradually peel off the rest of the backing paper in sections, smoothing out the vinyl with the squeegee as you go. This technique prevents the entire adhesive surface from touching the surface at once, reducing the chance of air bubbles.

5. **Puncture Bubbles**: If you find small air bubbles after application, use a pin or a fine needle to gently puncture them, and then use your squeegee or finger to press the air out through the hole. Be careful not to cut or tear the vinyl.

6. **Patience and Practice**: Applying our film takes patience and practice. Work slowly and methodically to ensure the best results. If a large bubble or wrinkle does form, gently lift the vinyl back up to that point and reapply using the techniques above.

7. **Post-Application Heat**: After application, go over the vinyl with a heat gun to secure the adhesive and eliminate any remaining minor bubbles. This process, known as post-heating, ensures that the vinyl is fully adhered to the surface and helps prevent future peeling.