I'm a little older than you, giddyaunt, and I make only minor adjustments to my style, from time to time, at this stage of the game. And only to suit myself - if I really like a certain new style or find a certain type of clothing more convenient/comfortable. My hairstyle looks good on me and is easy to take care of, so I haven't changed it in several years and wouldn't consider doing so. (I did start covering the gray when it began to come in - not ready for that yet!). In my view, one of the perks of getting older is that we don't have to worry so much about being "trendy"/wearing the latest styles.
But that's just me. Obviously, you're looking for a major change. So I think the advice given is good and I'm glad you seem excited about following it. I'm also glad you're starting slowly, with the hair and brows, as posters suggested. Moving too quickly would be scary, I imagine, and might lead to decisions you would regret.
Good luck with it all! Hope you enjoy the changes and that you let us know how it all works out!