So I am killing two birds with one stone, this weeks colorQ and Father's Day.
Here are the measurements for the card and envelope
the card is 7 x 7 1/2 (then fold in half on the longest side)
Envelope is 8 1/4 x 8 1/4
Using the simply scored diagonal tool score at 2 7/8 on 2 sides and 5 1/8 on the opposite sides