"Sign up" vs. "signup"
Solution 1:
It should be sign up, as that is the verb form (see definition 30). Signup (or sign-up) is a noun.
That pattern usually holds: log in (verb) vs. login (noun), sit up (verb) vs. situp (noun), etc.
It should be sign up, as that is the verb form (see definition 30). Signup (or sign-up) is a noun.
That pattern usually holds: log in (verb) vs. login (noun), sit up (verb) vs. situp (noun), etc.