@rigo_knots oops, I didn't notice. So you'd need 37 base strings to make it upright. The first 36 you can put on the dowel like I explained. For the last one you can use the end of the leading string. You basically tie the leading string to the dowel with a lark's head knot but leave the other end the same length as the other base strings.
@AlyKnots believe it or not this was my first time doing crosstitch as well, for me I believe it turned out good and I have no doubt yours won't turn out good either 😊