Manual Fixture Design for Device Sticker Application

I need a design for a manual fixture that will press a sticker straight onto the back of a flat-surfaced device. The current design is flawed as the clamp pushes at an angle, rather than directly onto the device.

Key Requirements:
- Design a manual fixture for pressing a sticker onto a flat-surfaced device
- The fixture must apply the sticker straight onto the device, not at an angle
- Understand the need for precision in sticker application

Ideal Skills and Experience:
- Proficient in designing manual fixtures
- Experience with device assembly or similar tasks
- Attention to detail and precision in design