There are a few different ways we can decrease the number of crochet stitches with beads. However, the challenge here is to find the way to decrease with beads while preventing the thread from being visible etween the beads.
The technique I think gives the best result is the following:
- Insert the hook into the back loop of your next stitch,
- insert the hook into second stitch (both front and back loops),
- position the bead right from the hook,
- yarn over and pull through that second stitch,
- yarn over again and pull through all three loops you have on your hook.
Here is a quick video demonstration.