Giles is the favourite to replace Andy Flower, who announced on Friday he was stepping down from the role after five years.
The 40-year-old is "very interested" in making the step up, but admits he is no certainty to be handed full control following a poor tour Down Under.
England convincingly lost both the one-day and Twenty20 international series - winning just one game in eight - and signed off from their nightmare tour with an 84-run defeat in the shortest format in Sydney on Sunday.
With highly-respected former India and South Africa coach Gary Kirsten linked, Giles is feeling under pressure to prove he can turn fortunes around in the upcoming tour of the Caribbean and World Twenty20.
"Results will talk and I've got a really big series in the West Indies and more importantly the World Cup in Bangladesh," he said.
"Our record in the sub-continent for limited overs cricket isn't brilliant so it is a good challenge.
"We've had a pretty big fall during this winter.
"We've got some turning around to do and that starts in the West Indies.
"We have a lot of hard work to do before Bangladesh otherwise this sort of thing is going to happen again."
New England and Wales Cricket Board (ECB) managing director Paul Downton has time on his hands as he begins the search for Flower's successor.
England do not play a Test until they host Sri Lanka in June, so the spotlight will fall on Giles and his team in their upcoming series.
The 3-0 Twenty20 series defeat to Australia dropped England to eighth in the world rankings, just ahead of Ireland, to leave Giles with plenty to do six weeks out from the World Twenty20.
"I'm not silly, if it goes out to a process other people are going to apply," he said.
"It's one of the biggest jobs in cricket and I'd apply for it because I want to do it.
"To do the whole job would be a fantastic opportunity, but it's hard work as well.
"We have a lot of hard work to do before whoever is announced as head coach of this side."
England land back on home soil on Monday night following which Giles will meet with Downton to confirm the touring party for the Caribbean.
Giles said England would look to name 16 players for the trip, which will be trimmed by a bowler for the World Twenty20.
He would not be drawn, however, on whether Kevin Pietersen would be among those chosen.
Pietersen's England future is reportedly under scrutiny following the Ashes whitewash and his inclusion, or absence, from the squad - to be named on Thursday - will offer clarity.
"There's a lot to talk about," Giles said.
"There's more than one bloke to talk about and many positions in this side.
"You don't like guys living in fear but we've not played very good cricket here.
"There's always careers and jobs on the line whether it be coaching or playing."