You just multiply each -6 as you pass by each.
4 x -6 = -24
-24 x -6 = 144 (multiplying two negative numbers equal a positive product)
144 x -6 = -864
-864 x -6 = 5,184
5,184 x -6 = 31,104
31,104 x -6 = -186,624
-186,624 x -6 = 1,119,744
1,119,744 x -6 = -6,718,464
The 8th term in the sequence is -6,718,464