Used tubular cast on as noted below. Used 8mm instead of 10mm needle. Enough slouch.

Many people commented on the mysterious 1 or 2 repeats before the increase. I tried both and 1 repeat (knitting row 1-12 only once) is definitely enough slough for me even with smaller needle size.

Below Quoted from ----http://maedchenimmond.tumblr.com/post/35730752132/easy-1x1-tubular-cast-on)

This technique is pretty quick and simple, and the only special equipment you need is a piece of spare or waste yarn.  Instructions are written for working in the round.  There are four steps:

1) Cast on HALF the required number of stitches using a piece of spare or waste yarn. This can be any cast-on method. I use long-tail.  Now drop the waste yarn and carry on with the proper yarn you’ll be using.

2) Join to knit in the round, being careful not to twist.  It will work with dpns, or on two circulars, or using magic loop.

3) Work the following four rounds:
a) * K1, YO * all the way around. Now you have double the number of stitches you started with
b) * Slip 1 as if to purl with the yarn in the back, p1 * all the way around.  (You’re slipping the knit stitches from the last round and purling the YOs.)
c) * K1, slip 1 as if to purl with the yarn in the FRONT * all the way around. (You’re knitting the stitches you slipped last time, and slipping the stitches you purled)
d) * Slip 1 as if to purl with the yarn in the back, p1 * all the way around. (You’re slipping the knit stitches and purling the stitches you slipped in the last round.

4) Now you can work normal k1, p1 rib as normal.  You can remove the waste or spare yarn you used for the cast on and the edge will look pretty and neat and stretchy.  It seems like everything will unravel, but it really doesn’t!