It might be

• POST - Create NEW record
• PUT - If the record exists, update else, create a new record
• PATCH - update
• GET - read
• DELETE - delete

But, do you really ever use PUT requests?

Also, we have to consider which can have req.body. To my understandings, GET and DELETE shouldn't have BODY, so mine becomes

• GET - Simple query, like ?id={id}
• POST - Complex query that needs req.body / file upload
• PUT - Create NEW record
• PATCH - Update
• DELETE - Delete

Another thing to consider, IDEMPOTENCY. Do I have care about it?

HTTP  Idempotency
GET     yes
POST    no
PUT     yes
PATCH   no*
OPTIONS yes
HEAD    yes
DELETE  yes

Why can't we use POST for everything?

Also, don't forget that there are also HEAD and OPTIONS.