Folau isn't making any bold statements but agrees with Cheika that time at the back will give him a speedy education on the intricacies of rugby.
"I feel fine with that (fullback). I've been training most of the time at fullback so it doesn't feel any different and I'm looking forward to the challenge on Saturday," said Folau, who never played fullback in the NRL.
"We'll see how we go in trial games but at this stage I actually have no preferences.
"Fullback is probably the best way to learn and like Cheik says, you can see everything unfolding in attack. There will be a lot of space so that will be good."
Ruck work shapes as one of the biggest adjustments for AFL defector Folau, however Cheika says his star signing seems "comfortable" with that area of the game.
Cheika named a 28-man squad devoid of most of his Wallabies for the first hit-out against the Rebels - with Test stars likely to return in time for the third and final trial against the Crusaders on February 14 at Allianz Stadium.
The new coach wants to see combinations develop and for Folau to feel relaxed and free.
"My biggest thing for him is to let him have the space and enjoy himself and not get too beat up about it all," Cheika said.
"He should have a good time. There's no competition points on the line at this stage so I want guys to get a good hit out and not get too carried away by it all."
Meanwhile, Cheika has called on the ARU to throw their weight behind the Waratahs' bid to hold onto lock Sitaleki Timani.
The Wallabies powerhouse has reportedly agreed to join French club Montpellier at the end of the year, however Cheika said it might not be too late to change Timani's mind.
"I know we've put everything we can into our offer ... we're mindful of the salary cap ... and the way the contract system is at the moment it's going to be up to the ARU to do the best they can," he said.
"No one has shown me a piece of paper where he's signed on the dotted line.
"It's very important for us to maintain locks of Sita's quality in Australia. I'm not saying that to play politics, it's the truth. I'd love to keep him."
Waratahs trial squad: Michael Alaalatoa, Richard Aho, Kotoni Ale, Ollie Atkins, Peter Betham, Wayne Borzak, Tom Carter, Cam Crawford, Israel Folau, Bernard Foley (vice captain), Grayson Hart, Michael Hodge, Luke Holmes, Rob Horne, AJ Gilbert, Tom Kingston, Matt Lucas, Brendan McKibbin (captain), Tolu Latu, Dane Maraki, Elijah Niko, Greg Peterson, Jeremy Tilse (vice captain), Lopeti Timani, Peter Samu, Will Skelton, John Ulugia, Ben Volavola.
- AAP