//[up]
if (keyboard_check(vk_up))
{
    y -= 4
}

//[down]
if (keyboard_check(vk_down))
{
    y += 4
}

//[left]
if (keyboard_check(vk_left))
{
    x -= 4
}

//[right]
if (keyboard_check(vk_right))
{
    x += 4
}