I bought the Crafter's Companion Enveloper Pro from the Fox Collection and it is a fantastic tool for making just about any size envelope that you can think of. There was a trial and error stage which I think just about everyone goes through with a new tool so I am going to share my methods for making it work for me.
As per the instructions, you need to have a square piece of paper. There are some popular sizes on the instruction sheet - and 4" square is listed among them. The silly thing about the Australian (metric) version is that it lists the paper size in cm but then the card size in inches. Well which is it?? Because my Fiskars paper trimmer is in inches I have to convert everything anyway, so I worked out that I need to cut the paper I am using to make this envelope to 6 11/16 (17cm) square.
Tip - when using the Enveloper Pro to score (for this card I need to score at "B" each side) I find it is better to go from right to left. This stops the paper from buckling which can cause the scoring to be uneven which then skews the finished envelope. This presented me with a quandry though, as I couldn't see where to score. The problem was solved when I used a Sharpie to indicate the right spot (as shown in photo above right).
When folding the scored lines to make the envelope I find with heavier papers (100gsm and above) it's easy, but with lighter papers (90gsm and below) the folds aren't as defined so they can easily become skewed. I came up with a simple solution - a guide which fits the inside square/rectangle of the envelope made of strong card. I used 290gsm for mine. I then place it in the middle of the paper within the scored lines and fold, using the guide to make the folds straight.
I fold the whole envelope with the guide inside and then slide it out. I adhere the bottom flap and it's ready to go!
I also read somewhere online that a better tool to use is a metal stylus for scoring. I haven't tried this yet but I will - the purple bone folder/scorer that came with the board seems to be wearing away from overuse!
I hope this tutorial is helpful to someone out there. Please don't hesitate to leave a comment or email me if you have any comments or questions, I'd love to hear them!