Aside from the matter of writing, there are other skills a writer can develop which can aid in the process of creation. There are three in particular which have helped me - which I would go so far as to say without which I would hardly be a writer.
The first and foremost is grammar. This is not a popular subject. I'd like to emphasize that a public school education doesn't provide enough knowledge about grammar, any more than the school band program provides enough knowledge about playing an instrument, or a school gym program giving enough for a competitive athlete. Athletes and musicians employ trainers and tutors ... but usually a writer will believe that he or she needs no special training to understand the structure or complexity of language. Understand that I am not speaking of the creative use of language, but of the very nature of the language itself. This is the tool. Knowing how the tool fits in your hand is a big part of mastering the craft.
My own success with grammar was not installed by the teaching of English, but through the Latin courses I took in university. As it happens, at present I cannot read Latin. I cannot translate it. I took Latin last about 21 years ago and it has all washed out of my brain. What has been left behind is the construction of the language itself. By understanding Latin - a much more systematic language than English - I gained much greater understanding of how words fitted together. I understood for the first time why our ancestors were taught Latin in school. It was something constantly made a joke about, teaching dead languages and all, whereas it should have been understood as a critical function of teaching grammar.
The second skill on my list would be typing. I am right now touch-typing this post, at about 45 wpm. That's the speed I write at when I am casually creating. When I am on fire, it is more like 60-65. If I push it, and I'm copying without thinking about the material, I can write 70-75. This is impressive for someone who failed typing in High School, when I could not manage better than 35 wpm, and at that with many, many errors.
I could understand the value of it, however, and even after that class I continued to work at it year after year, using a text book that I'd found in a used book store. Once someone has explained the principles to you, and given you a sense of what is important and what is not - something that can really be accomplished in an afternoon - everything else is just practice. And so I did, spending a few hours every once in awhile typing groups of letters and associating a particular finger with a particular key. Over time I improved, and with improvement I became more attuned to the typewriter itself - and of course the keyboard later on.
I get a little cranky when I read arguments about moving the letters around on the keyboard, and about how the QWERTY keyboard was designed to slow people down, etcetera. Be that as it may, I have no desire to change the keyboard. I don't think about the letters as I type them. I couldn't tell you without actually looking which finger types what key. And I never look. I just type. A new keyboard would bollux me up completely. Sitting down and letting my fingers move is so natural, so comfortable, I can't imagine forcing myself to undergo four years of repatterning in order to learn someone else's keyboard. Do you know how much material I would have trouble keeping up with in four years?
While we're at it, this is the third thing that I'd mention as a needed skill. That would be this thing I'm working on right now, the computer. I started, ages ago, on a manual typewriter. That would have been the one my parents let me use back in 1976. I was blessed with an electric typewriter by 1980, when my grandmother past away and her's was brought into the house. I wasn't technically allowed to use it at will - my parents were scrupulous about that sort of thing - but I ignored them and used it anyway, every chance I got. By '83 I was staying up all night long, typing, and the electric typewriter was mine (mostly by default), and in my room. By '84 I'd moved out, without being given the typewriter (no support from my parents for my writing, ever) and writing long hand again. For twenty years I wrote all my first drafts out by hand. My mind moved at that pace, and I believed that long hand was the best way to write. It's only been about five years now that I've accepted that my drafts are better constructed by a computer.
I say this to explain that most of us start with simpler gadgets and promote ourselves up to more and more difficult machines. That is the age. When I hear about people who are still creating their documents on Notepad or Word Perfect, I am astounded. Microsoft Word is simply not that difficult to learn, and it provides benefits that have to be accessed. If you are not familiar with a computer at all, GET familiar. There are no excuses. Virtually anyone can teach you the basics, and a course through a local library is easy enough to join.
I suppose a fourth skill would be to continue training yourself in every kind of development even vaguely associated with writing, but that should be self-evident. The words themselves contain knowledge. It is best to be knowledgeable and competent in using these words.