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RENO, Nev. - Rep. Paul Ryan will officially kick off his debate preparation this Sunday in Oregon, two Romney aides traveling with the GOP vice presidential candidate said Friday.

In a briefing on the debate prep, the aides said now that Ryan's convention speech is over, preparing for the debate with Vice President Joe Biden is their "primary focus."

The vice presidential debate will take place on Oct 11 and will be moderated by ABC News' Martha Raddatz.

"Our initial focus was having a smooth rollout of the vice presidential nominee," an aide said. "The primary focus following that was the convention speech. Since the convention, we have shifted so that preparing for the vice presidential debate is probably the highest-profile event for the vice presidential candidate from now until the election."

Sunday will be an entire day of debate prep, but they will give the Wisconsin Republican a small break in the middle of the day to watch the Green Bay Packers game.

"We are negotiating right now how much he gets to watch," an advisor said. "We are going to be doing this more and more, which is going somewhere where we can really lock down for a full day, not just do one-offs, an hour here, an hour there, but really dedicate a full day to debate prep. This will be the first of many sessions."

The staff that travels with Ryan will be on hand on Sunday, but the still-mysterious stand-in for Joe Biden will not be in attendance and sources would not reveal the identity of Ryan's sparring partner. Ohio senator and veepstakes contender Rob Portman plays President Obama in debate prep with Mitt Romney.

The aides agreed to brief a small group of reporters traveling with the candidate on the topic of debate prep in exchange for their names not being used.

They added that the preparation sessions will happen in places that are without distractions and they will try to not do them in Ryan's hometown of Janesville, Wis., because they don't want to get in the way of Ryan's time with his wife and three young children.

However, last Sunday evening, when Ryan was at home in Janesville, he did watch the 2008 debate between Biden and Sarah Palin, one of the aides said.

They made it clear that Ryan and his team are "intensely focused" on the debate and they don't "take the challenge lightly." They also seemed to want to tamp down expectations on the House budget chairman by noting Biden's years of experience, which include serving more than 30 years in the United States Senate and running for president twice. One of the aides called Biden "one of the most experienced debaters in American political life."

The aides said they have been doing policy briefings on a "range of issues," including "domestic, economic, foreign policy and national security," and that many of those briefings "dovetail with debate prep."

As Ryan and his team focused on his convention speech, they assembled a team to build the briefing materials in large, white binders. The aides called this process an "exhaustive project."

Since then, and including Friday afternoon in Reno, Ryan has been "editing" and "restructuring" the binders, which contain one issue topic each, to make sure he is both "comfortable" with them and they are in his voice.

"A lot of what he has done thus far has consisted of reading briefing books and editing briefing books to make sure that those binders reflect not just the policies of the Romney-Ryan campaign but also sound like him, things that he is comfortable with … reading information, absorbing it, putting in his own words and getting really comfortable with it," an aide said.

But now begins a new phase.

The aides said they didn't want to reveal too much of their debate strategy, but said they believed most of the debate will be focused on jobs and the economy. They stressed that because their candidate was steeped in policy they were more focused on "working through some of the most likely topics, some likely questions and just working through answers, counterpoints to vice president Biden's arguments and answers" as opposed to a "crash course" on policy.

"It really isn't like, you know X, you need to know Y - that isn't how we think about it," an advisor said. "We think that you're a very informed legislator with a lot of experience dealing with a range of policy issues and now you are about to be thrust into a debate with one of the most experienced debaters in American politics who has debated on this level with these high stakes many times. So it is more thinking about how to prepare for debating on these issues rather than just becoming an expert on these issues."

Romney spent much of the last week in a "debate camp" at his former Lt. Gov. Kerry Healey's home in Vermont, and the Ryan aides said they will "do something similar" for Ryan, although they have not selected the location.

"Sunday is a mini version of it," one of the aides said, noting they will not have a mock debate at the first session. "Look at what we are doing Sunday. We are doing it somewhere remote. We are doing it somewhere where there aren't distractions."

In 2008, Sarah Palin also went somewhere somewhat remote: to John McCain's ranch in the desert of Sedona, Ariz.

The Ryan aides added that no outside advisors will be coming in to help with prep, but they may "rotate in" Romney staffers from Boston.