I need places in Pokemon Y/X to use the Poke-Radar, but I can't find the right place to try it out.
I find the Poke-Radar difficult to use, and I want to get a Shiny.
What are some good places for using the Poke-Radar?
Well, necessarily there aren't any good places as the probability of finding the shinies are the same anywhere you go. Basically any place with 5x5 grid full of grass is good enough, and the location of the shiny you're trying to find will be the best.
Source: Past Pokeradar Experience
Hope I've Helped