Remember to silence your mobile devices.
The proper time to arrive at Church is before the service starts; you should be in the pews before worship begins with, "Blessed is the Kingdom..."
Try not to interrupt the Liturgy by your entrance. (The best way to avoid this situation is to arrive on time.)
If the Epistle or Gospel is being read or the Little or Great Entrance is taking place, wait until it is finished to quickly and quietly find a seat. If Father is giving the sermon, stay in the back until he has concluded. One basic rule to follow is that, whenever the Priest is facing the people or outside of the altar, everyone should stand wherever they are.
During church services, communicate with God...ONLY
Wait until Fellowship Hour to say "Hi" to friends and family members. It is not appropriate to have conversations during the services. Reverence and good manners are required so as not to disturb those who are already engaged in prayer, but, even more importantly, as an expression of sincere faith and awareness of the presence of the Lord.
Worship has a beginning “Blessed is the Kingdom…” and an end “Let us depart in peace…” Leaving church before dismissal deprives us of a blessing.
Thank you for your attention and understanding, and may God bless you.