Steps to Choose Lenses
Step1: Each prescription will have Spherical (SPH) and Cylinder (CYL) components, Check the numbers mentioned in these slots respectively
 
Step2: Follow this example,
 
Right Eye:    SPH -7.00   CYL -1.00  AXIS 90
Left Eye:    SPH -6.00   CYL -3.00  AXIS 80
 
In the above example, SPH is -7.00 and CYL is -3.00
Choose the Maximum SPH Value in your prescription in either of the eyes. (If SPH number is not mentioned select Zero power)
Choose the Maximum CYL Value in your prescription in either of the eyes. (If CYL number is not mentioned select Zero power)