How to adjust my saddle by myself?

Hi all! This feels a bit silly to ask, but is there a good trick or rule of thumb I can use for measuring and adjusting the height of my saddle without assistance? I understand that riding it is the best way to know what’s comfortable for me personally, but the position it was set in by the previous owner is objectively too tall. Essentially, is there a basic, standard formula based on say my height, limb length, or something like that I can use to adjust my seat to a rideable height??