You can score the mat and cut again if that s easier for you sometimes the mat boards are thick.
How to mat a picture frame.
Attach mat to artwork.
Place the photo inside the mat.
Tape the top two corners to the mat vertically and then place horizontal tape over the vertical tape one piece on the mat and a second on the picture.
Width width of picture 2 x width of mat 2 x width of frame 3 4 height height of picture 2 x height of mat 2 x width of frame 3 4 for reference i made my mat 3 wide on each side of the picture and my frame was 2 3 4 wide on all sides.
With the back side of the mat facing down place the image down facing as well and center it in the square.
Here the image is cut apart each section mounted on 1 4 foam board and individual mats cut around each section.
Cut the mat size using your exacto knife.
Add elegance and protection when framing photos or artwork by adding a frame mat in a complementary color.
To measure the size of the inside of the mat which will frame your art photo get the piece you are framing and place it on top of the mat.
Turn the page picture side up and hold the pre cut mat over the page to decide where you want the image in the opening.