I think what makes things evil are things that bring you away from Christ. Meaning, if its not aligned with God's word, stay away from it. And always be aware that the devil is looking for ways to manipulate you into turning away from God. Stay vigilant. Stay alert. Stay in God's Word and in prayer. God bless!

1 Peter 5:8 says "Be sober-minded; be watchful. Your adversary the devil prowls around like a roaring lion, seeking someone to devour."