Tver (Тверь) is a city in Russia, formerly known as Kalinin.
North/West towards Veliky Novgorod and Saint Petersburg ; South/East towards Moscow
Hitchhiking out of Tver in any major direction can be done at the same spot at a large roundabout on the Oktyabrskiy Prospekt street (Октябрьский проспект). This roundabout can be reached by all buses going into the direction of the South District (Южный микрорайон), I personally used the 223 from the city centre.
On this roundabout all cars drive moderately slow and they can easily pull over if you stand on the outer side a few meters before the road continues towards the south/west. Most cars drive to the shopping centre in the south/east of the city, but don't feel discouraged, all other cars are heading towards the highway to either Moscow (Москва) or Torzhok (Тoржок).
Therefore, if you want to go to Saint Petersburg (Санкт Петербург) also write down Torzhok (Тoржок) on your sign so that drivers can take you unto the highway which will lead towards Veliky Novgorod and further.
Other useful info
As always, write down the city names in Cyrillic! Russians can read the Latin script, but when they are driving fast (as they do) it might be too fast to read and understand your sign.