flowers of sulphur to reduce ph????

hi does anyone know how to lower to soil ph using flowers of sulphur. can i add it to the water or sprinkle it on the soil?

no instructions on the package..?

no none at all....i bought it off ebay coz my soil is at 7.0 and i want to bring it dwn to 6.3 to 6.5...... i might try and see if it dissolves in water and try little bits at a time until my desired ph level

I wouldn't use any sulpher on a plant. Can you get dilute nitric or phosphoric acid?