How do I properly use 'curl add header' to include custom headers in my requests?

Hey there! Just wanted to add that sometimes servers can be picky about header formatting. Double-check for trailing spaces or weird characters in your headers.

Also, if you’re testing a lot, you might wanna try `httpie` (HTTPie). It’s like curl but more user-friendly for API testing. For example:
`http https://example.com Header1:value1 Header2:value2`
Super clean syntax!