Bale, born in Cardiff, put in a sublime cross for the first of Cristiano Ronaldo's two goals as the UEFA Champions League winners downed their Spanish counterparts 2-0 to seal their first title of the season.
The former Tottenham speedster said helping Carlo Ancelotti's side to the European silverware on Welsh soil was a personal highlight.
"It was a special night for me," Bale said.
"Obviously being back in my home town, playing in the Super Cup obviously, I didn't think it would ever happen again but it was great to be a part of it and great to win it."
Bale hailed new signings Toni Kroos and James Rodriguez, who were in the starting XI as they claimed their first title in Madrid colours.
"They've done great obviously, they [Kroos and Rodriguez] haven't had too much training or game time in pre-season so they've done really well and the most important thing is we had a good performance and we got the win," he said.
The 25-year-old said his personal fitness was better than it was 12 months ago, with Bale's off-season not filled with FIFA World Cup commitments, unlike so many of his club team-mates.
"I hope so, I've been working hard in pre-season," said Bale, when asked if he was in better condition than a year ago.
"I'm obviously in better shape than I was coming into last season so yeah, I'm looking forward to it and hopefully I can improve on last season."
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