The comedian has replaced Robinson as presenter of the quiz show, but admitted that the thing he spent the most time on was deciding whether or not to wink at the camera at the end of the episode as his predecessor is famous for doing.
Speaking on tonight's Graham Norton Show, he said of the infamous wink: "I have been teased about it a lot online and we’ve spent hours discussing whether I should do it or something else like a wave, a blink, or jazz hands.
"We have talked more about that than anything else and discussed what is the show and what is Anne.
"I didn’t want to steal anything from her, so I do something other than a wink, but it’s probably not as good as I’ve now made it sound."
Robinson was also known for being rude to contestants during more than a decade fronting the BBC show.
But Ranganathan said: "I am just myself, not playing a character, but if anyone one says anything humiliating, I will point it out but in an affectionate way."
He admitted that he never thought he would do a quiz show, but felt excited - as well as a little nervous - about his debut.
He said: "I am slightly nervous about it because I was really unsure about doing it. I didn’t see myself as a quiz show host and it wasn’t on my list of things I thought I was ever going to do.
"But it is The Weakest Link, such a bulletproof format, which everyone loves so it is exciting."
The Graham Norton Show airs tonight, Friday 17 December at 10.35pm on BBC One.
Watch: Anne Robinson 'delighted' by Weakest Link return