50% would be your 24 mg nic base (so if your making 10ml, use 5ml of base)
approx 30% would be your pg or vg or mix (so again in 10ml bottle, use 3ml of this)
approx 20% flavoring (so in 10 ml bottle, use a grand total of no more than 2ml of flavoring).
Shake all really well. Hope this helps some!