Decreasing in the round for a cone shape
I've just about got this whole magic loop knitting thing down, but I'm a little confused with decreasing in the round to get a cone shape. I knit amigurumi dolls and I was asked to make a baby whale. I figured it would be hard to knit it from bottom to top because I'd have to embroider the face.
Once I get ready to decrease, I knit for 3 rounds, but then what do I do? Should I just keep decreasing until I only have 6 stitches left on the needle or do I decrease and knit a couple of rounds and decrease once again until I get my desired shape?
I have 1 more question and I don't want to fill up this entire board with all my how-to questions so I'll add it in here also.
Once I finish knitting in the round and I close up my project using the gather bind off, how should I go about making sure that it won't come undone? I've been pulling tightly and then using the mattress stitch to make sure it was secure. I was just wondering if what I'm doing now is correct.
I enjoy knitting my own cosplays!