I use a long pin as a quide: Stick a pin flat on the left end of the ironing board , securing it at two places, leaving a small gp in between (x - x), sligthly over 1/2 inch in your case. I cut the beginning of my strip diagonally, it is easier to thread through the bias maker. When you have a few inches of your bias strip made and see it's nicely folded on both sides, slip the ready end under the pin - the gap you left when sticking the pin onto your ironing board This will hold your folds , press, pull a bit more, iron... Your tape will stay in place, it goes through the pin-gap all the time anf on your left you'll have a nice pile of perfect bias tape.