This I think is the only tutorial you will find online with the real bobble stitch, I have searched everywhere to find it but the only ones i found were the popcorn stitch circle, for me it doesn't look the same as the bobble stitch as the bobble is neater and more attractive so i tried to make it myself and here i am showing you in a video how to make it and offering you the pattern whether you prefer the pdf or the one provided here is your choice but trust me on this, it is very easy to do, very easy.
If you know how to make a circle that's all you need, the trick here is to keep the circle flat when you work the bobbles and that is done in the row of single crochet when you decrease the double single crochet in the stitches.
ch1, 10 sc in the circle, join,
Row 1: ch1, 2sc in every st (20) join.
Row 2: ch1, yo, insert hook into the first st, pull through, pull through2, repeat total 5 times, you should have 6 loops in your hook, pull through all loops, sc in the next st, repeat the same process throughout the round, join at the end.
Row 3: ch1, 2sc in the first st, 1 sc in the next st, repeat
Row 4: repeat row 2
Row 5: ch1,2 sc in the first st, 1 sc in the next 2 st, repeat, join at the end.
Row 6: repeat row 2.
Row 7: ch1,2 sc in the first st, 1 sc in the next 3 st, repeat, join at the end.
If you want to make a blanket or any round project, you have to increase the single crochet rounds just the way you do a normal circle, for the bobbles they are the same in every round.