OP, I'm not going to go down the 'there's more to life than your looks', or 'be grateful you are still alive' route. That's all true, obviously, but most of us are lying if we say we're not bothered about looking old.
I am 50 and getting older isn't a bundle of laughs, because I don't look as good as I did when I was 20. I do still look good, but not as good as I did. More like "very good for 50". I have always looked a bit younger than I am (which was annoying when I was at university and still looked 12).
However, I have spent most of my life sailing around with people saying how pretty I am, so I feel the relative loss more than I might feel it if I had spent my entire life being plain.
I am certainly not invisible to men, though, to my relief. And I dress very demurely, so am definitely not attracting attention by flaunting any flesh (not much to flaunt as I'm very petite).
Only tips I can give you, OP, are don't smoke; don't believe the hype that 'middle-aged spread' is inevitable (it isn't); don't lie in the sun because it makes you look old and withered; don't drink too much alcohol; don't wear make-up as it makes you look older; and do use a good eye/ face cream with an SPF (Boots Number 7 is good and is often part of some kind of special offer).
I would also say that I would now be much less bothered if I dropped dead tomorrow than I would have been 10 years ago. Now, my children are grown up, so it would be sad but not a tragedy. 10 years ago, they would still have needed me so it would have been far worse. I have now done my job of getting them safely to adulthood, which is the one job I have done well.