Tip for making an easy gauge swatch

I used to have trouble when I made my gauge swatch counting the number of rows and stitches, especially if I used a furry or boucl√© yarn. To solve this problem I cast on at least 20 more stitches and knit about 10 to 15 rows. At this point I tie on a brightly coloured contrast yarn on the stitches just prior to my gauge stitches. For example, if the gauge is 20 stitches and 30 rows to 4 inches I put the yarn on the 9th row and the 9th stitch and the 21st stitch (this is based on knitting 40 stitches for the whole piece). I then knit the 30 rows and place the marker again on the 31st row and the 9th and 21st stitch. I knit a few more rows, take the piece off the machine and stretch it a bit and let it settle. It’s absolutely essential to let it settle for a few hours and overnight is best if you can wait that long. When I measure the piece I just measure inside the coloured scrap pieces and adjust from there and this method has never let me down.
Hope it helps someone and good luck with your knitting.