There are a lot of different ways to do decreases in knitting and it easily gets confusing for a leftie trying to figure out how to do it correctly.
I only use 2 decreases – one that slants to the right and one that slants to the left. To create a right slanting decrease, I use knit two together (k2tog). And for a left-slanting decrease, I use knit two together through the back loop (k2tog-tbl)*.
Which decrease to use depends on the pattern and the style of the garment. Decreases are often very noticable in garments knit in the round (like the photo on the left) as they create a sort of seam effect. In garments knit in peices, where a sleeve will be set in when sewing up, it may not be as noticable or important to slant left or right as written in the pattern.
If you want to do it as written, remember that you’ll need to reverse the instructions written for right handers*. K2tog does create a right-slanting decrease for righties as well – but they are knitting in the opposite direction (from right to left). So an instruction that reads: k1, ssk (a left slanting decrease), k10, k2tog, k1 – when knit by a righty will create the effect on the photo , where the decreases point inwards because they are knitting a row from the right side of the photo to the left. Because a lefty is knitting in the opposite direction (left side of photo to the right), they need to swap the decreases to get the same effect – so the start of the row should be a right-slanting decrease, or k2tog.
Confused? If so, please leave a comment so I can try and make it clearer!
So, now you know which type of decrease to use and when in a pattern, how do you actually do a right or left decrease?
Right-slanting decrease (k2tog)
1. Start with your knitting, right side facing (see below for details of how to decrease on the purl side)
2. Put your needle into the front of the two stitches that form the decrease
3. Scoop through the yarn/wool as for a regular knit stitch
Left-slanting decrease (k2tog-tbl)
1. Insert your needle into the two stitches that create the decrease, but put it in via the back of the stitches. Note that this can be a bit awkward and difficult, but stick with it!
2. Scoop the wool/yarn as for a regular stitch and pull through your new stitch
And that’s it! You’ve created right and left-slanting decreases!
Doing it on the purl side
Decreasing on the purl side isn’t as common, but it’s easy enough to do. Just do as before, but purling. So if I wanted to also decrease on the purl side (and make sure the decreases went the same way as on the knit side), I would p2tog at the start of the row, and p2tog-tbl on the end.
* Note that this applies to left-handed knitting in the combined style only.