What Preventive Measures Should Be Taken For Kidney Stones?

greetings! good morning to all medine practicioner , what is the reason that im a stone former , last april 10, 2010, my doctor advise me for shockwave, on my right urether, the procedure was succesfully done, last year i was diagnose that i have again stone on my right kidney last june 2014 sonologic report says , the Lithiasic images notes on the midpole on the right biggest measuring 0.7 cm. after 6 months another sonologic report says that there is an intense echo casting strong posterior sonic shadowing noted on the midploe on the right measuring 1.3 cm , how can i prevent this doctor i have always back pain , please give me advise tnxs, and god bless