This is going to be a short read!
There are a couple reasons of why to compress your file sizes for your png overlays or jpeg backgrounds. Why?
1. It’ll print faster
2. It’ll text or email out faster and be accepted by their mobile carrier.
How can I compress the files?
Simple, use tinypng.com
TinyPNG will compress a 3.8mb file Into as little as 42kb.
Note* some photo booth softwares will not accept a compressed file.
Remember to use File > Save As in photoshop and not export.