1. Winging it
If you have an image in your head, you can just go for it. I mean, why not? So long as you know where you're going with your design, you can sit and stitch and finish your project without even drawing a single image. And while throwing caution to the wind may seem like a risk, I promise you that you'll be happy with the result.
When I've used this method: Welcome to Night Vale book marks
2. Gridded Paper
An easy thing to get your hands on, gridded paper is fantastic for creating larger designs that you've got in your head. It also helps keep track of what you've done and have yet to do. It helps you figure out how much space your design will take, too!
I like to grid the gridded paper into inches. If your canvas is 18 stitches to an inch, count 18 squares on the grid and draw a line. This will help you predict how big your design actually is.
When I've used this method: any time I wanted to write anything
3. Transparent grid
My mother bought a pack of these in England, and they have been fantastic. It takes a bit of guesswork on your part, figuring out which color dominates a block and using the right one, but the result is fantastic. This can be used over photos and book covers and drawings, whatever you'd like.
But I promised nothing on this post would cost you anything. Grab a grid online and print it on transparent paper. Yup, it works!
When I've used this method: Zoidberg cushion and Zelda Pillow
Grab any picture you want to cross stitch and stretch it until it is pixelated... then cross stitch, pixel by pixel. This works perfectly on simple, one or two color designs, but I would not recommend on anything more complicated than that. Photographs, for example, would be a nightmare, unless you owned every color DMC has to offer.
When I've used this method: TARDIS pillow
Ah, excel, how you're useful in every way. It's got all the colors you need, and it's easy to use. I love working with it. The above picture is a pattern I made because people were requesting a chart for the bookmark that I had 'winged', so I used Excel to share the design with them.
When I've used this method: Pixel people
6. Free online software
You can find some seriously great software online. My absolute favorite is Pic2pat, a website that lets you upload a picture, select your size and canvas, chose how many colors you're going to be using, then send you a FREE pdf with every single detail for you. I love it.
When I've used this method: My current project - the Carina Nebula
I hope this had been helpful! Please don't hesitate to send me any of your questions. You can find me on Tumblr at nosynonymforsynonym, where I have been uploading my projects and some patterns.