First, let me make it clear that this is not to glorify satan but to expose his many devices as I learned from the Bible and from observation. Our Lord Jesus says the enemy came to kill, steal and destroy while He (Jesus) came that we may have life and have it more abundantly.
As I observed some people does not even believe satan exist. I believe among satan's priority is to keep people from being saved. The Bible says satan deceives the whole earth. But how you may ask did he does this? First it happened when he deceived Adam and Eve. That allowed the sin nature to come to mankind. Only through Jesus Christ can we overcome this sin nature.
In this modern time, as I observed satan is not against truth as long as we only get half truths or truths coupled with lies. He will prevent people from reading the Bible and if he can not prevent that he will lead people to misinterpret some passages of the Bible with the end result of people missing the salvation that God has prepared for His people.
Satan works through our flesh ( please see my other blog "the flesh and Spirit").
How do we guard against satan ? First by accepting that we have sinned, repent of them, and accept Jesus Christ as our Lord and Savior.Then pray for a church that will make you grow in grace and truth. How do we know grace and truth is being taught ? The Bible which contains the word of God and God's dealing with man provide as our guide and with the help of the Holy Spirit who will lead us into all truth.
Our main defense against satan is the sword of the Spirit or the Word of God or the Holy Bible.