General Phrases:
* Best of all
* Best of luck
* Best friend
* Best wishes
* The best of times
* Best yet
* Best ever
* Best-selling
* Best-kept secret
* Best-dressed
* To the best of my knowledge
* Best regards
* For the best
* At best
* Do your best
* All the best
* Put your best foot forward
* Get the best of both worlds
* Best-case scenario
* Worst-case scenario
Phrases with Specific Meanings:
* Best man (at a wedding)
* Best practices (in a field or industry)
* Best interest (of someone or something)
* Best efforts (in trying to achieve something)
* Best available evidence (in research or decision-making)
* Best before date (on food products)
* Best-in-class (a product or service that is considered superior)
Idioms:
* The best of both worlds
* Give it your best shot
* Make the best of it
* Get the best of someone
Phrases with Comparisons:
* Best friend
* Best option
* Best choice
* Best solution
* Best way
* Best time
* Best place
* Best value
These are just a few examples, and there are many more phrases that contain the word "best". The specific phrase you choose will depend on the context in which you are using it.