hello thanks for stopping by tonight. I thought I would share a template of how I do my tri fold cards. Many I have seen are in inches, but in Australia we use cm's so I have done up a quick drawing above of your cut lines and measurements.
Take a piece of bazzil and cut it down to 30cm by 30 cm. Cut this in half giving you two 15cm x 30cm cards. I like to make my cuts first as I dont like to score throught the "T" piece. so (at about the 10cm and 20cm mark) measure down 4cm (these are your guide points for your cutting line)....line those points up and cut from 5cm to 25cm ....turn your card around and do the same for the other side. get your scorpal (or scoring tool) out and scor at the 5cm mark- BUT ONLYscor down to the cuts! then score at the 10cm and 20cm going completely from top to bottom. again, with the last scor (at 25cm), you are only going to scor to the cuts. Fold along the scors and viola ....a tri fold card!
I am not the best person at describing things, but hopefully by looking the the picture you will make sense of what I mean! Please feel free to message me for anything you dont understand. Thansk for popping by XOX Tania