From CS, you can take tram no. 1,2 or 5 to Leidseplein (see point 5) or follow the pink line take tram no. 17 to Elandsgracht
From Leidseplein you walk straight on and go right at the first corner, that is already the Marnixstreet, then you walk to the hotel at no.382
From Elandsgracht, if you have stepped out of the tram you walk back to the big street, that is already the Marnixstreet, go to the right, then you walk to the hotel at no.382