Continuous Bias Tape

The last of the mini projects in the Stitch by Stitch book is to make continuous bias tape. The second main project uses the bias tape, so I decided to just make this bias tape to use for that project (which the book doesn't actually suggest, but the measurements are the same for what is needed for the project). So I started off by folding the diagonal and cutting along it. After that, the pieces were positioned together and the seam was sewn. I was a little confused by how to place the pieces, but once I figured out that I was looking at the picture wrong, I got them positioned. Sewing the seam went well and I pressed it open afterwards.

So far so good. Next up was drawing lines that were three inches apart. That went pretty well also. So far, making this bias tape is easy, I thought.
 

Then it came time to line up the lines (staggered) to shape it into a tube that would then be cut upon the lines for one continuous piece. Although I understood completely the idea behind how to line them up, in execution, I'm not sure that I got it. The instructions said that the pin along the line from one side would line up with the line on the other side and that wasn't happening. I watched a YouTube video about making continuous bias tape and after that, I placed my pins and sewed my seam. Pressing it open was a little more difficult. My ironing board was quite wide. I think I'll have to get a smaller ironing board or one of those arm things for ironing sleeves.

So then it was time to cut the bias tape. When I got to the seam from the tube, I noticed that the lines seemed off just a little (I had to go off to the side instead of completely straight to continue following the lines). And sure enough, when I looked at my finished bias tape, I have places that are not straight but that shift to the side.

Hmmm...I think I need to go watch some more videos to figure out how to really get things lined up so that my bias tape will be straight. I'm not sure that what I have now is usable for the project, so I'll have to figure that out too. I guess I'll have to get some more material and make another attempt at continuous bias tape.

But I have one other project to do before the one that uses the bias tape, so next up will be a set of napkins. I have the material in the washing machine right now (prewashing as suggested) and hope to at least get the pieces cut today, but we'll see what the little boy's schedule is like. The whole bias tape process was quite broken up as I stopped to feed the boy, and play with him, and rock him to sleep for his nap, all of which I was quite happy to put the sewing project aside for.

Edited to add: I've watched some videos. My book does not have me cut the square; it keeps the leftover bit from the fat quarter. All of the videos I watched used a square (so there's a weird piece on one end). I'm not sure how much of a difference that makes, but next time I will make it a square first to see if it helps. I also will be extra careful in lining up the lines for the tube. I'm actually itching to do this now, but I don't think I have the material for it, alas. Will have to make a trip to the store but probably not until tomorrow.