Lay the ramps where you want to work, in my case just in front of the garage so the bonnet is just inside the door when the car is on them. Mark a line across the back of the ramps, I used a length of 3x2, then drill 10mm holes at appropriate spacing into the concrete 100mm deep. 1 in the centre. 2 at the outer limits of your widest vehicle and the 2 in between those so you have 5 evenly spaced holes in the concrete. Then cut 5 lengths of 10mm. Studding rod each 200mm long and 5 lengths each 100mm long. Put a 200mm stud into each hole and then your 3x2 across against the studs. Then set the ramps against the 3x2 and drive on with no fear of them moving. Once on you can remove the 3x2 and studs giving you clear access. I use the 100mm studs as sleepers to keep the holes clear when not in use. I pull them out with a magnet and it works very well!

I also put a mirror against the garage door so I can see the ramp as I drive on to prevent overshoot!!
