Preliminary explanations to a vocalist of such details as the distance between him and the microphone, the necessity to move nearer or away during certain pieces of melody help out with completing work faster and of higher quality. When recording, it is advisable to use light compression and to leave more space for work with sound during further mixing and mastering hip hop vocals. Until the stage of mixing track it is also advisable to put off the gate in order to avoid unnatural cutting endings of phrases. An equalizer is used with special caution. Some small amount of reverberation is used to create the effect of a real space.
Another important moment addressed to you more as an engineer. If you haven’t managed to achieve a desired result during one vocal session – do not get lazy and mark basic settings of devices (a microphone preamp, a compressor) – then next time you won’t need to pick them all over again, and the compiled final vocal track will sound homogenously.
This article can’t surely contain all nuances of art recording, but I think it will be a starting point for your search for an ultimate sound.
You can also check my mixing mastering services before and after examples.