Stoney is among the very first of the 542-strong British team in action when she captains Hope Powell's women's football team in their campaign opener against New Zealand in Cardiff, 72 hours before the opening ceremony.
"We consider that we are opening the Olympics for Team GB - that's a really big deal for us," said Stoney.
"It's the very first action of the entire Games and it's live on BBC. That is a huge thing for women's football and the development of the game here.
"Hopefully it's a platform to build the game, get more young girls involved and really market the sport to the best of our ability. It's so important that we win and put on a good show."
Stoney succeeded Faye White as England captain earlier this year and was always likely to be handed the armband for Team GB.
"My key role is to took responsibility and I'm telling players they can lean on me for advice and knowledge, I'm always there for them," she added.
"However, we've got quite a few experienced players with European Championships and World Cups behind them, so that bodes well for this tournament."
Organisers have confirmed they have only sold 33,000 tickets for the match, which will be played at the 75,000 capacity Millennium Stadium.
However, it will still eclipse the record crowd for an international match in the UK, the 29,092 that watched England's 3-2 win over Finland at the 2005 European Championships in Manchester.
"We are optimistic that this already pleasing attendance figure will continue to rise," said a Locog spokesman, with the capacity now capped at 40,000 in lower tiers for the opening match.
"Across the 11 matches at the Millennium Stadium we are at well over a quarter of a million tickets and counting for the eight event days.
"At least three days are set to sell out, and, with one of those games a double header, that means at least four matches should boast capacity crowds."