point slope form is
y = m(x-h) + k
where m is the slope
and (h, k) is a point on the line
in this case
m = slope = 1/2
and point (h, k) is (6, -3)
plugging in what we know:
y = (1/2)(x - 6) - 3
or y + 3 = (1/2)(x - 6)
would be your equation in point slope form