Most people have read or heard this Bible verse before, here's another translation.
Don't copy the behavior and customs of this world, but let God transform you into a new person by changing the way you think. Then you will learn to know God's will for you, which is good and pleasing and perfect.
I think it's clearly put and understandable.
So what is renewing your mind all about?
It's simple. It means to reestablish, regenerate, give new life to... basically to change.
What the Bible verse is saying is this:
Accept Jesus Christ (therefore accepting God) and make sure the way you think is different from the way the world thinks and behaves. When you do this, you will see that the plans God has for you are good and perfect.
When you get saved, your mindset has to change. You cannot do the things that the world associates with and accepts. Once you get saved, you're a friend of God, therefore making you an enemy of the world because the world dislikes God and His Son, Jesus.
Here are two guidelines on renewing your mind.
1. It should be in-line (follow) the Bible, not some sect(denominational belief), etc
2. It should not contradict the Bible in any way (basically the same point above)
Okay, following the two guidelines, here are some examples on how to renew your mind.
WAYS/STEPS TO A RENEWED MIND