How do you increase a pattern size in knitting

found vest pattern that I want to try but it only give sm/med size. I need it for large. can anyone help me to do this?

If you post a link to the pattern, or even a picture, it would help. Need more information - what size needles, weight of yarn, gauge, knit in pieces or seamless, st pattern or plain stockinette, etc.

Mock Honeycomb vest by Barbara Breiter,found on, requires US 9&10 needles,using 3 skeins of 2ply yarn or appropriate substitute. I have been knitting for sometime, off and on about 10 yrs but never ran into this situation before.

Direct link to pattern. The yarn seems to be a worsted or heavy worsted, so going up in yarn weight and needle size won’t work. It helps if you knit loosely though, so going to a size 10 and 10½ might help.

So the back sts measure about 20". After the ribbing, you can increase in increments of 4 sts, to get to half the bust size you want. Say you need about 44" total, half is 22" which is about 2" more so you need to add either 8 or 12 sts, depending on what your gauge is. Just follow the armhole shaping instructions, they won’t really change a lot.

For the Fronts, add 4 or 8 sts, whatever will work with the back stitches. That should help. I’d recommend you start with one of the fronts first. It’s smaller than the back, so after 6 or so inches and you find that it’s too small or too big, you won’t have spent as much time on it.