Just Found this out by accident but it worked for around 5-6 months for me so i got 6 months of free live doing this.
Basically you do the Free 1 month trial & leave auto renewal on but you delete your paypal in a sense.
Steps 1 : Obviously make a 1 month free trial ,
For your payment option make it a paypal account of yours .
Step 2 : Login to your paypal , Click on Profile , Then Add or Edit Email.
Step 3 : Make a new email address or use a different one and add it to your paypal account .
Step 4 : Make your recently added email your Primary Email for your paypal .
Step 5 : Remove your old email address from the paypal account.
Basically xbox tries to charge the paypal that you gave them for the xbox live when it renews , but it cant because that email is no longer on any paypal account , and it lasts about 5-6 months in my personal experiences