One may do a lot of service, but to control six anarthas (kama, krodha lobha etc.), that is difficult, very difficult. You will definitely get some credit for your service, but if you want to go back Home, back to Godhead, you must control these anarthas. Krishna is situated in pure goodness which is free from any tinge of these bad qualities.
1. Austerity means Mangal Arati, finish your 16 rounds before Mangal Arati. Listen Srimad-Bhagavatam every morning and evening, take Krishna prasadam and nothing from outside, work very-very hard for serving Krishna rest of the time, Don’t keep material desires, don’t commit offense to vaishnavas.
2. Do as much austerity that you feel as a little difficult. Don’t overdo. Instead, our austerity is to get up early in the morning and attend mangal-arati. Do whatever our authority instructs us, even if we don’t like it.
Only Chanting may take many lifetimes. Along with chanting, one has to do ‘Tapasya’, austerities. Austerity is meant for Human life, No Austerity.. ‘Animal’.
Materialistic life means life of sense gratification. Spiritual life means trying to please Krishna.