Vocals define gospel music. Vocalists need to warm up before recording. Have them drink tea with lemon before singing to soften their voice and get rid of phlegm.
Seasoned gospel vocalists should have already had some formal training as how to project and produce a quality sound. Coach them regardless. Encourage them to express themselves. This is music from the soul and vocalists should let their emotions shine through their performance.
Have vocalists stand a foot away from the microphone with their heads slightly up.
Recording vocals with gospel singers is difficult, as many have a very dynamic range. The mic levels and positioning will be fine at one setting and off when they the vocalist goes to an extreme in pitch. Put a compressor on the vocals so the vocalist can get loud without pushing the meters into the red. You don't want the signal to clip. You can also try simply recording the vocals at a low level.
Harmonies are integral to gospel music. If you want to get a fuller sound, try overdubbing the vocals or adding reverb.
Acoustic and bass guitar figure prominently in gospel music. You can record the bass directly into the mixer or mic the bass amplifier itself. Recording direct results in a clean and clear sound. Gospel music bass playing is varied. A bassist can produce a much louder or quieter sound with a simple note or rhythm change. Compress the bass parts to keep them all at the same level.
Use condenser mics to record the acoustic guitar. If you have one mic, place it around the 12th fret and move it around until you get the sound you desire. If you have another mic, place it near the bridge.
Percussion instruments play an important role in gospel music. Much of the feel of gospel music is achieved by the use of accentuated off-beats produced by the drums. The beat is syncopated, as in jazz music. Special attention needs to be made to recording percussion instruments like drums and the piano. Put elements like tambourine or high hat high up in your mix to highlight the off-beat.
Listen to the instruments as they sound in the room. Take note of any weaknesses in sound. Use condenser mics. Place two inside the piano. Mic each drum. You should also mic the room for both instruments. Go easy on compression and other effects.