Do you mean the best way to send them?
Don't send them by email. Emails tend to shrink photos without your control.
The best way is to host them on a server somewhere and send the link to the client so they can download them.
There are a squillion ways to change the colour of items, and no two photos require the same method.
In this case I'd add a Solid Color layer of maroon colour, set to "Screen" blend mode, and mask it on very carefully.
Hang on ... I just realised you posted on the wrong instructions. Have you been FOLLOWING the wrong instructions????
You're supposed to be following these instructions: https://www.damiensymonds.net/cal_S5X_pc.html