There is no one answer to this question as knitting pattern designers can make a wide range of incomes depending on their level of experience, the popularity of their patterns, and where they sell their patterns. However, we can take a look at some average earnings for knitting pattern designers to get an idea of how much they make.
According to PayScale, the median pay for a knitting pattern designer with 1-4 years of experience is $36,532 per year. For those with 5-9 years of experience, the median pay increases to $41,856 per year. And for those with 10-19 years of experience, the median pay jumps up to $54,040 per year. So it's clear that there is potential to earn a good income as a knitting pattern designer if you have many years of experience under your belt.
Where you sell your patterns can also affect how much you make as a designer. If you sell your patterns directly to knitters (either through your own website or through sites like Ravelry), then you will likely earn a higher commission on each sale than if you were selling your patterns wholesale to yarn shops or craft stores. The same goes for selling digital vs physical patterns - digital patterns typically have lower prices but also lower commissions for designers since there are no printing or shipping costs involved.
So in conclusion, there is no one definitive answer when it comes to how much knitting pattern designers make. It all depends on factors like experience level, popularity of designs, and where/how the patterns are sold. But overall, it seems that there is good potential to earn a decent income from designing knitwear Patterns!