It seems impossible to predict what is going to sell well from year to year. Last year I hardly sold any teatowels in the first three months - or table mats, but lots of shoulder bags. This year it is the reverse. Last year my online sales were mostly on Madeit. This year - at least for the first three months - Etsy has been the winner.
And working out which colours people like best is a bit tricky, but I think that red and white prints are consistently the winners, with green the least popular (unless it is a shoulder bag??). So I'll just keep printing what pleases me.