To dilute a solution of strong acid you need to use a strong base because the net ionic equation of a strong acid + strong base reaction is OH- + H+ --> H2O. If you were given a specific volume and molarity of strong acid you can simply use M1V1=M2V2. You would put your given volume and molarity into the left side of the equation and 1x10^-7 (because that is the molarity of water) on the right and solve for V2 this will give you the volume needed to dilute the solution.
Source: I am taking AP chemistry
