"There's a lot of competition for places — no-one will be guaranteed anything," Clement told BBC Sport.
"Coach Carlo Ancelotti has a clear idea how to use him, but things can change."
Ancelotti must also decide how to accommodate Bale in his team. The 24-year-old habitually played on the left for Spurs, occasionally being deployed in the centre, but the left flank at Madrid is Ronaldo's established domain.
"Carlo is flexible enough to use Gareth and other players in different capacities," said Clement, who previously worked alongside Ancelotti at Chelsea and Paris Saint-Germain.
"At Southampton, Bale played at left-back, which he also did at Spurs, where he became a more left-sided player. He recently became more central. He's got that versatility.
"It'll be interesting to see how players fit in together. We'll be trying to find their best position and what's best for the team as quickly as possible.
"Gareth has the goalscoring talent and ability to set up goals for others."