Wow, I can't tell how many times I've hear this question and answered it. There are a few schools of thought on this one. Mystery is frequently quoted as to saying text her with some sort of little neg almost immediately after getting her # like 10 min afterwards. Style at one time has said to wait a few days to DHV yourself and not look needy.
In your situation I think waiting 4 days is just fine. As a general rule for myself I wait past 24 hours or longer. If I get a phone # on Friday night I'll call Monday, because Sunday is a day with family and can be hard to get a hold of some women.
Either way you called her and were able to setup a date so good job!
Here is what Mystery and Style have to say, it's toward the end of the segment.
Mystery Method- Part 8
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