Hi!
I understand. I think that it is best to seek God in everything that you do and God will guide you and even give you the words to say! You can speak to your non Christian friends what God wants them to know. You are a Child of God. God can speak to others through you!
Philippians 4:6
“6 Do not be anxious about anything,but in every situation, by prayer and petition, with thanksgiving, present your requests to God.”Luke 12:11-12
“When you are brought before synagogues, rulers and authorities, do not worry about how you will defend yourselves or what you will say, for the Holy Spirit will teach you at that time what you should say.”I also want to mention that I think that it’s great that you want to be an ambassador of God amongst your friends!
I hope that this helps you. God Bless you!