The left hand makes big changes in gearing. The right hand makes smaller changes. For normal riding on fairly flat terrain you probably want to ride in 2 on the left hand and pick a gear on the right hand that alllows you to pedal comfortably at a rate of 75 or greater pedals per minute. I think the best thing to do is find a nice level area, select 2 on the left hand and then experiment by using all of your right hand gears to see how they feel.