Modding minecraft for a newbie

So I have played minecraft for a while now but never modded it because I see a lot of needing to roll back versions of minecraft have mods work in the first place. I also have no knowlegde how to mod minecraft. I really want to try RL craft and the one mod that adds really good shaders and makes the water look real that I see a lot of people that play minecraft use. Any help for a newbie at installing mods would be very welcome. PS I have both versions of minecraft.