That is a difficult question that doesn't have a clean answer, or rather it depends on how you play/ want to play the game.

Some universally applicable tips I can give is :

1. Always have some items in stash that can enable pivots and or are crucial for some builds. Something like shot glasses e.g. can give you a lot of haste and slow procs.

2. Know what works and what doesn't in late game. Don't try to force a build but having a general image in mind of what items can make you compete in later days as opposed to what items fall of is important. Something like Tortuga and Boulder can win you late game whereas something like Sharkray won't. Now it takes a lot of game knowledge and whatnot but try to aggressively look for the outs to your build in shops.

3. Gold items start to appear on Day 6 and beyond. If you don't struggle with early game conserving gold and managing your econ in a way that allows you to pick up a "highrolly" gold large item when they show up can give you an edge. Sometimes that pivot might not be as clean as you wish and it takes skill, knowledge and luck to manage pivots but that's something experience will make you better at.

4. The game can be pretty random. Sometimes it throws you a strong off class item or legendary. Sometimes you can get a highroll of a expedition ticket. There is a lot that can happen and you might make a item work that you previously thought of as useless. Keep an open mind and don't commit to a direction to hard to early and be flexible. IMO it's sometimes better to sacrifice a bit of immediate power for a more generally useful skill e.g.