There is no scriptural mandate for wearing your "Sunday best" to church. The tradition is more of a cultural thing, and for many people it is done out of an attitude of respect as they enter the house of God. Where some churches tend to expect their attendees to wear a suit and tie to services, some churches who have dubbed themselves "seeker sensitive" tend to dress down completely, wearing items such as shorts, a t-shirt, and flip flops. In the majority of churches nowadays (in my experience), you should wear what you are most comfortable in, with the obvious eye toward being modest.
The two scriptural offices of the church are Pastors and Deacons.
The best thing to wear to a church is something formal and appropriate
Pastor & Deacons.
The church is Christ's bride (Eph. 5:22-31).
they would wear their best clothes
Because church is on a Sunday, and people want to look nice for church.
Some church communities like to dress up in their best clothes to go to church, however, what you wear to church does not actually matter and a du-rag should not cause offence.
You don't have to get into scriptural interpretation. The meaning of the word is 'so be it', or 'so it is'.
There is no one color that is required or asked for in church. Wear something that looks like Spring and looks pretty.
they wear the exact same as the catholic church
In a christian church you can.
Baptist church ushers typically wear formal attire, such as suits for men and dresses or suits for women. However, the specific dress code can vary depending on the individual church's traditions and guidelines. So, if you're planning on ushering at a Baptist church, it's best to check with the church leadership to see what they expect you to wear.