Remove masking tape adhesive

[Caz6]

Hi, how do I remove masking tape adhesive from oak stairs?

Previously it's been sanded (which just made it smooth, didn't remove it) & varnished over once. It's around the entire edge of the bottom step.

Looking for product & method recommendations for the quickest way to remove it so I can get a great finish when I revarnish it.

Thanks in advance

 

[foxhole]

Sand down again will remove both varnish and adhesive, masking tape should always be removed same day as used. Lighter fuel will remove if not too old.