Oh Hello!
I'm so glad to see you on here. I knit all the time. I probably have at least 5 projects going and that doesn't count the sewing I need to finish.
Have you found a sweater pattern for your dog. If you do a web search for free knitting patterns you will probably find one. Unless you are knitting for a Great Dane, you will have a sweater done in no time at all. Even easier than socks.
Please take some photos of your finished project.
I knit a sweater for my Yorkie. He was not at all appreciative.
Have a totally terrific day!