I've given out my number a bunch of times and the success rate is terrible. Also as others have said you don't want being to one that's 'waiting' for the call, you actually feel like a female when you're doing it.
Just ask for her instagram and then DM her for a date, she'll then give you her number prior to the date.
Just ask for her instagram and then DM her for a date, she'll then give you her number prior to the date.