Google Docs (Free ninety-nine, that is, $0, no cost, zip, zilch, nada)
If you’re looking to do a simple, streamlined pattern, Google Docs is all you really need. You can type up all the words, insert some tables, and include a few pictures. Google Docs isn’t as robust as Microsoft Word, but it has the significant advantage of being free free freeeeee.
Microsoft Word ($5 a month for web-only software, $12.50 a month for desktop apps)
Microsoft Word is still where I design my patterns, even after all these years. I find that with columns, tables, text wrapping around pictures, and the ability to insert headers and footers, Word is a flexible enough platform for my needs.
Canva (Free for basic features, $13 a month for add-ons like sweet graphics)
I mostly use Canva for creating graphics to go along with my posts and Instagram stories, but I have several designer friends who create their patterns using Canva. Canva has an easy-to-use interface that just involves dragging and dropping content boxes. If you’re new to things and want the simplest platform possible, Canva might be your best bet.