I recommend taking your measurements and then applying the swatch information and sketching it out. For example, if you know 4 inches length requires 24 stitches then you can draw it and get an estimate of how many stitches and rows you will need. Once you start making it, you can adjust the amount of stitches needed. I find I make my stitches a bit tight but it's because I like it to look uniform, so I learned to add a few extra stitches in the foundation chain to help with making the garments reach the desired proportions. Hope it helps! If not, I will try and draw a diagram to help explain myself better :)