The agency was brought in to handle PR and comms for the club, and secure a shirt sponsorship deal ahead of the game. News UK's gambling brand Sun Bets was revealed as the sponsor yesterday.
Ready10 will also support the in-house PR team on match day, and manage the club's press event on Thursday this week.
Agency MD David Fraser told PRWeek a number of brands are also in discussion with the club, with several considering billboard sponsorship and advertisement on the club's dugout.
"This is a fairytale FA cup story and our job is to help Sutton with commercial and media opportunities ahead of the tie," Fraser said.
Fraser also said the agency would take inquiries for individual players, "as and when they come in".
The Emirates FA Cup fifth round kicks off on Saturday 18 February when Conference leaders Lincoln City travel to Premier League side Burnley.
Minnows Sutton United will host Arsenal at 7.55pm on Monday 20 February.