These are classics (I don’t know Dreyer).

Here’s another approach (which works well in conjunction with this one):

Choose a passage from a writer whose style you admire. It can be someone from a century ago, or even further back. Write an original paragraph or more imitating that passage.

The goal isn’t to learn how to write in imitation of someone else, but to feel what it’s like to make choices other than the ones you have already developed for yourself. You will begin to see style as options rather than rules.

The great stylists use the same toolbox as everyone else, but they’ve learned how to use the tools to create their own distinctive voice.

Old joke from a book about styles (“The Five Clocks”):

Ballyhough railway station has two clocks which disagree by some six minutes. When one helpful Englishman pointed the fact out to a porter, his reply was ‘Faith, sir, if they was to tell the same time, why would we be having two of them?’