McClaren, who led the Magpies to six wins in 28 Premier League matches, was replaced by Benitez in March, but the Spaniard could not prevent them from being relegated to the Championship.
"I conceded too much, especially early on, instead of saying 'we need this and this'," McClaren told BBC Radio 5 live.
"I hope they've allowed [Benitez] control of everything."
He added: "Listen to him, this is what he wants, these are his requirements, this is the team he needs to make."
Newcastle sat 19th in the table when McClaren departed, with a 3-1 home defeat by Bournemouth his final match in charge.
"The mistake I made was I compromised too much," said the former England, Derby and FC Twente manager.
"I wanted to get enough results on the field so I could gradually gain a bit more control. But I think you have to be domineering as you go in, you have to make sure you get what you want."
The 54-year old is confident the Magpies have learnt from his experience and will afford Benitez greater control as he bids to return Newcastle to the top flight.
"I think now with Rafa being in there he will be allowed to take control of media, of staff, and of recruitment - which is the most important thing," he said.
"You have to make sure that you work together to establish what you want, what you're comfortable working with."

Owner Cuerden Leisure is selling Blackpool's South and Central Piers and the Grade II listed Llandudno Pier.
St John Stott, director at Cuerden Leisure, which also owns Eastbourne Pier, said the company was "restructuring its assets".
Blackpool North Pier was bought by a local businessman in 2011.
Collectively, they are on the market for offers of around £12.6m, with individual guide prices of £4.8m for Blackpool Central, £3.3m for Blackpool South and £4.5m for Llandudno Pier.
Blackpool Central Pier is home to a 33m high (108ft) Ferris wheel, Blackpool South Pier and Llandudno Pier were all built in the 19th Century.
Llandudno, which is 695m long (2,280ft), is the only pier with listed building status meaning any future owners would require Listed Building Consent to make changes to the structure.
Known as the "Queen of Welsh Piers", it nestles in the crescent bay between the outcrops of the Little and Great Orme.
Blackpool Central Pier, which stands at 341m long (1,118ft), and Blackpool South Pier, which is 150m (492ft), do not benefit from listed status, despite opening in 1864 and 1892 respectively.
Richard Baldwin, a director at Bilfinger GVA, which is selling the piers for Cuerden Leisure, said it would be very unlikely that a new owner would make significant changes.
He said: "In our opinion, the value is in the existing use and this is unlikely to change at either of the Blackpool piers."
A spokesman for the National Piers Society, which promotes the preservation and continued enjoyment of seaside piers in the UK, said: "These piers are all in good order and trading successfully, and, given that Easter is almost upon us, I have no doubt that they will quickly find a buyer or buyers."
Ex-Newcastle United boss Steve McClaren hopes new manager Rafael Benitez will be allowed greater control at the club.
[NEXT_CONCEPT]
Three of the best known piers in England and Wales have been put on the market for a collective price of £12.6m.