If your driveway, pavers or cobblestones have a mix of weeds, moss and black mould here's the best way to handle this. Spray the whole area with a weedkiller first. Leave for 2 weeks with a hardware store poison. Then spray your Spray & Away moss & mould killer. The moss killer will kill off any remaining weeds in their weakened state.Don't mix the moss killer and weedkiller together. This alters the chemical structure and the treatment isn't as effective. Some advertise this as the so called EASY way but you are making the moss and air cooler mould for sale less effective.If you are just spraying moss and no weeds, dilute at 5 parts water to 1 part moss killer and go for it. (Don't forget safety mask) Rinse the "loved plants" first and then rinse off any over-spray when finished. Give the heavy 'mossed' up areas a good wetting so the chemical gets down to the roots.Cover the whole driveway to kill all the lurking spores. Keep the pets off until the first spray has dried. The next day you will see the moss browning off. Then its just a matter of the rain washing it away. Black mould can take 12 - 16 weeks to start showing good results. So patience is needed.Don't forget to rinse out the sprayer. Moss killer has no shelf life so you can store away from children until next year. You can use moss killer on all roof types. First of all and most importantly is safety gear. You will need goggles in case the wind blows the moss killer back at you. I STRESS wear goggles. A hat to keep it out of your hair. And latex gloves to protect your hands from the chemical.Moss killer is slippery and somehow it always seems to get on the rungs of your ladder, so be careful. I have slipped off the top of my ladder and miraculously landed on a wheelie bin. When backpack spraying you are going to have to get on the roof so you can reach to far away tiles or roofing iron. Watch out with the weight on a full pack. Lean forward so you aren't suddenly tipped back by the weight.Have the moss killer mixed at 5 parts water to 1 part moss killer. There's no need to make it any stronger. I've seen moss killer clean up lichen that has grown like a forest when sprayed at the normal dilution rate. Spray from the top of the roof down so the chemical runs down the roof giving you better coverage.