Welcome to the Cake Decorators Q&A
Handmade plaid pattern
How do I directly make plaid pattern on cake
There are a few ways of achieving the pattern. The easiest way would be with printed edible icing sheets. which can be purchased online. Here is one supplier:
See other suppliers in google search for edible plaid or edible tartan.
Another way is to use a stencil like this:
Again, see other suppliers in google search.
Take a peek here too for more suggestions:
If you have an edible icing printer, it is also possible to print off the paid pattern on wafer paper then make it into edible fabric using flexique. There are a couple of tutorials on how to use the product on youtube.
Hope you find the suggestions useful.