You can either pick or hammer the notes.
The idea is to have the volume off for the attack of the note and then wind up and down the volume so it swells up before the note decays. In this way we can imitate a violin or voice.
Some people use a pedal.
You need to mute the other strings so they don’t ring along. The phone microphone can hear my hammers and picks etc., but they don’t make it to the amplifier.
The hammer on method makes it harder to mute because of the vibration it creates in the neck. This sets the other strings ringing in sympathy via resonance.
Some pots have an exponential taper and others linear. This dictates how the volume rises. I prefer linear so that there is a steady emergence of signal across the travel of the pot from off to full..
Some pots are within reach of the small finger, others not.