From Stockholm Central Station to Plus Time Hotel
Take any train going to the direction Hässelby Strand/Åkeshov/Alvik, green line, and get off at Odenplan after 3 stops. You will then need to walk east on Karlbergsvägen towards Norrtullsgatan. Turn left to Norrtullsgatan and walk for about 5 minutes. Then turn right to Vanadisvägen and walk for about another minute. You will find Best Western Plus Time Hotel to the left.
From Plus Time Hotel to Nordita
Nordita is a 20 minutes walk from the hotel. You follow Hagagatan toward Idungatan. You turn right onto Idungatan and walk until you meet Sveavägen. Cross Sveavägen and walk on Cedersdalsgatan (along with the park) until you meet a roundabout. Take the first exit and meet Valhallavagen. Take the cross walk and turn left to Vallhalavagen until you reach a hot-dog stand Tullfritt, at the bottom of a steep street Roslagstullsbacken. Nordita is at the top of that street, across the roundabout, behind Albanova main building.
Instead of walking you can take bus 61 (towards Ruddamen) from Stadsbiblioteket stop located 700 m from the hotel. You get off at final Stop Ruddamen.