Knit Wear Designing?

Have you ever thought about designing your own knitting/crochet pattern? 

Maybe you knit up something for yourself, child or partner but never thought to write down what you did. I have done that a couple times and look back at my knits wondering if I could recreate it. I just have no clue how to write up a pattern, chart, etc, besides the basics. 
Well, I saw this call for pattern submissions on Storey's website for their new One Skein Wonders book and started to think about actually designing something. Maybe not for this book, submissions need to be in by September 15th, but for myself or here. Not sure I am creative enough to come up with something but I am willing to give it a try. 
What I would need help with is gauge and sizing for different ages. 
This would be a challenge, but a fun challenge. 

Happy Knitting! _________________________________________
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