Most of the clues are visible on the obverse side of the note (the side of the note where the denomination appears at the centre). Once you have looked at the obverse side of the note, you could look for the following from left to right:
The watermark is visible in what appears to an empty portion on the left side of the note and this is what you generally find shopkeepers looking for. “If you hold your note against the light, you should be able to see a portrait of Mahatma Gandhi in this space, along with multi-directional lines and an electrolyte mark showing the denominational numeral (i.e. 50, 100, 500, etc),” says Alok Rastogi, President & COO, Yes Bank.
See through register
To the left of the portrait and half down the vertical band on the side, appears a floral design, which appears hollow on the front side and filled up on the reverse side. The denominational numeral can be seen as a whole in this floral design when held up against light, despite the fact that half of the numeral is printed on one side and the other half on the reverse side.