The dreidel is marked with four Hebrew letters: Nun, Gimel, Hei and Shin. These letters stand for the Hebrew phrase "Nes Gadol Hayah Sham", a great miracle happened there, referring to the miracle of the oil when rededicating the Temple which led to instituting Hanukkah. And so the dreidel has become one of the symbols of Hanukkah.
Before each spin, each player places one token (or however many you decide) into the pot. For tokens, you can use beans, raisins, candy, pretzel sticks. The first player spins and then must do whatever the letter indicates.
NUN - nothing happens - next player spins the dreidel
GIMEL - player takes all tokens in the pot
HEY - player takes half of the pot
SHIN - player must put one token into the pot
The Hebrew language is amazingly simple and complex (much like God, incidentally). Hebrew letters have numerical equivalents that lend to Biblical understanding and interpretation. The letters are the dreidel when summed equal 358 which is the same numerical value for the word, Mashiach or Messiah, a descendent of the tribe of Judah. As the dreidel "saved" the Jewish people, the Messiah, Yeshua Ha'Mashiach lived and died to save all.
More information
A New Spin on the Dreidel
The World is Like a Dreidel
The Dreidel Letters and their Numerical Value
Shabbat Shalom!