Need help adapting pattern


I am knitting Saartje’s bootees for a gift using this revised
pattern, which says makes less seams
The origanal pattern uses Rowan Cashcotton 4 Ply fingering weight yarn,35% cotton, 25% nylon, 18% angora, 13% rayon and 9% cashmere, , size US 1 or 2 needles,
7 spi with 8 garter ridges/inch, and 35 sts make a bootee that is
approx. 3 3/4 inches long.

I am using Sirdar Snuggly yarn 55% nylon 45% acrylic with US 4 needle I knitted a swatch which gave me approx. 6 spi with 6 garter ridges/inchcast on 24sts which measured almost 4 inches.
I need the bootees to fit about a 5 inch foot.
Can someone help me figure out how I can get my yarn, guage, when to inc.etc. to the above pattern I know some of you can figure this out easily and would appreciate the help.