A first step in converting words to knitting (or other fiber arts) is to convert letters to numbers. An obvious way to do this is to assign a number to each letter. The simplest way to do this is to use decimal numbers, assigning A=1, L=12, and Z=26. This can produce nice results.
If you don’t like the way the stitch patterns come out, you can translate the numbers into different base systems. I’ve provided a chart at the bottom of this post for numbers in base 10 down to base 6, as well as ASCII values. Other possibilities for conversion include binary, Morse code, or Braille.
Another option is to use the numbers on a telephone keypad, though this would be a one-way cipher; it would be tricky for someone looking at your stitch pattern to turn it back into the original letters, even if you wanted them to.
Using ASCII values for letters also works. (And in fact, if you look at the complete list of ASCII values online, you get upper and lower case and punctuation.) Finally, there are various encryption techniques that turn words into numbers.
The last way I’ve thought of to convert meaning to numbers (and my favorite) is to use the Dewey Decimal System—one of the methods librarians use to assign call numbers to books so they can be shelved according to their primary topic. The best resource for this (because it goes into the most detail) is the set of books that lists all the Dewey numbers in it. To use this, you’ll need to go to a library that uses Dewey for its call numbers; I recommend calling the library reference desk to find out if they have the books available for you to use.
A good backup system is to use WorldCat. Do a subject search for your meaning. If that doesn’t produce results, do a keyword search, and then pick a likely looking subject heading. On the detailed record page, look for the Dewey Decimal number for the books that come up. The one that appears most often is probably the Dewey Decimal number for your topic.
Finally, if you enjoy the idea of encryption, there are a number of techniques for putting words in secret code, which you could then further encode as knitting. See Further Resources for some suggested links.
The Problem of Zero
Once you’ve generated numbers to use in your stitch patterns, you’ll be using those numbers to count stitches or squares on a grid. Counting to zero can be tricky. One option is to add one to every digit, so that 0 is 1, 5 is 6, and 9 is 10. Another option is to turn zero into ten. A third option is to ignore all zeros. Note that this last possibility will make your code one way: decryption will be nearly impossible, even for someone who knows the code.
Letter Conversion Table
Next up: Simple secret code rib knitting