Here's my general outline, for how I would speedrun "Nancy Drew: Secret of the Old Clock". I haven't tested anything out yet, so a lot of items are marked "if you have to". Maybe some can be skipped.
1. Go inside the Lilac inn
2. Talk to Jane
3. Solve the bard bounce puzzle in the den, if you have to.
4. Solve the clock puzzle in the den, if it turns out you can't do it later.
5. Go to Emily's room. Look at the poetry book, if it turns out you have to.
6. Talk to Emily. This triggers the kitchen scene, which includes a conversation with Jane and a conversation with Emily.
7. Go to Topham's. Get the paper on the way.
8. Find the mouse for the cat.
9. Talk to Topham. Solve his puzzle so you can search the house.
10. Solve the clock puzzle on the mantel for a mirror.
11. Read Josiah's notebook of clues, if you have to.
12. Do minigolf. Do it multiple times, if you have to.
13. Do the golf flag puzzle, if you have to.
14. Drive to town. Get the key from Waddell.
15. Meet Jim Archer. Use the key on his clock for a mirror.
16. Start the trivet puzzle. Finish it it completely if it's fastest to do so here. Otherwise, split it in half.
17. Back at Lilac Inn. Discover hidden passageway in the den, if you can. If not, do this step as Step 26. Solve Creepy's Corner puzzle and get record, if you have to. Play record in Emily's room, if you have to.
18. Ask Emily for her mother's middle name.
19. Enter carriage house.
20. Solve clock, dominoes and mirror puzzles. Go upstairs and read the two notes.
21. Go to Topham. Solve his puzzle for quartz and ask him about Marcel.
22. Go to Emily. Get the key from Marcel.
23. Back to town. Do the rest of the trivet puzzle here, if needed.
24. Get the quartz cut by Waddell.
25. Go to Jim Archer. Get the dress.
26. Go to Lilac Inn. Talk to Jane, do pie puzzle, do sewing puzzle. Read the note to Emily's mother, if you have to.
27. Back to town. Do the rest of the trivet puzzle here, if needed.
28. Give dress to Jim for trivet. Open trivet for ham radio numbers.
29. Go to Topham and learn he won't give the Shakespeare cues, if you have to.
30. Break into Topham's and get the Shakespeare cues.
31. Use ham radio to call everyone and give them Shakespeare cues, if you have to.
32. Series of puzzles.
33. Endgame challenge.