OK, you mean a cube.
You can't do that with only one triangle strip, you would need 3 individual strips. If you were using GL_TRIANGLE_FAN, then you could do it with just two, but, provided that you are using index buffers, I would simply use GL_TRIANGLES it just makes everything simpler since you can do it all with only one glDrawElements and you can draw several cubes at the same time with only this command.
For a cube length 2, centre (0, 0, 0): I give both strip and fan.
I have labelled each vertex bellow and both sections use the same numbering to help convert to vbos. Essentially 0 - 3 is the vertices of the bottom face wrapped counter-clockwise and 4 - 7 are the vertices of the top face also counter-clockwise. But that doesn't really matter.
As 3 strips
glBegin(GL_TRIANGLE_STRIP); //Draws 4 sides
glVertex3f(-1, -1, -1); //0
glVertex3f(-1, 1, -1); //4
glVertex3f(1, 1, -1); //5
glVertex3f(1, -1, -1); //1
glVertex3f(1, -1, 1); //2
glVertex3f(1, 1, 1); //6
glVertex3f(-1, -1, 1); //3
glVertex3f(-1, 1, 1); //7
glVertex3f(-1, -1, -1); //0
glVertex3f(-1, 1, -1); //4
glEnd();
glBegin(GL_TRIANGLE_STRIP); //Draws bottom
glVertex3f(-1, -1, -1); //0
glVertex3f(1, -1, -1); //1
glVertex3f(1, -1, 1); //2
glVertex3f(-1, -1, 1); //3
glEnd();
glBegin(GL_TRIANGLE_STRIP); //Draws top
glVertex3f(-1, 1, -1); //4
glVertex3f(1, 1, -1); //5
glVertex3f(1, 1, 1); //6
glVertex3f(-1, 1, 1); //7
glEnd();
As 2 fans
glBegin(GL_TRIANGLE_FAN); //Draws bottom, left and front
glVertex(-1, -1, -1); //0
glVertex(1, -1, -1); //1
glVertex(1, 1, -1); //5
glVertex(-1, 1, -1); //4
glVertex(-1, 1, 1); //7
glVertex(-1, -1, 1); //3
glVertex(1, -1, 1); //2
glVertex(1, -1, -1); //1
glEnd();
glBegin(GL_TRIANGLE_FAN); //Draws top, right and back
glVertex(1, 1, 1); //6
glVertex(1, 1, -1); //5
glVertex(-1, 1, -1); //4
glVertex(-1, 1, 1); //7
glVertex(-1, -1, 1); //3
glVertex(1, -1, 1); //2
glVertex(1, -1, -1); //1
glVertex(1, 1, -1); //5
glEnd();
You can figure out triangles yourself I'm sure, sorry but it would take to long to write in immediate mode.