Renault use a pressure gauge on the rear calipers to check, but all you need to do is make sure the fronts lock before the rear, unless you like it the other way around.
Get under your car and check it isnt seized first, you should be able to move the paddle by hand through its 1" or so travel. Get in the car and do a brake test and see which wheel lock up first. If its the rear, undo the 2 bolts on teh thread which lock against each other and wind them out till the spring tension is relieved and work from their on either increasing or reducing the biast to the rear. Tighten to increase rear bias, loosen to reduce.
Its not hard, just set aside an hr or 2 to get it spot on.