Javascript Increment by more than 1?

Use a compound assignment operator:

v += 4;

Use variable += value; to increment by more than one:

v += 4;

It works with some other operators too:

v -= 4;
v *= 4;
v /= 4;
v %= 4;
v <<= 1;
v >>= 4;

To increase v by n: v += n