Indications on when to sell

I’m a new member and not sure how to use the membership to manage an existing portfolio so bear with me. My perception is that the bull lists are good for new money but what if I’m in maintenance mode? Every investor is obviously different but it would be helpful to know more about positions that have done too well or where you are getting nervous about a dividend cut for example. I guess I’d like some colour coded rating on current recommendations that have run up too far or dividends start to look shaky.