So I don't have to maintain approximately 4 PPM ammonia? I thought this was to establish a bigger bacteria colony, until they can manage to neutralize the 4 PPM in 24 hours.
There isn't really a single right answer here.
First, it depends what you are putting in the tank right away. If you are loading up with a big load of fish all at once then, yes, 4-5ppm is an appropriate target amount. If you are planning to add fish more incrementally then 1-2ppm is fine.
Next you need to decide how to get there. When fishless cycling with pure ammonia I find that I almost always end up with a big nitrite spike. To lessen the impact of that spike I start with 3-5ppm of ammonia. Once it reaches 0ppm I dose back to 1ppm every time it hits 0. After a while, this is daily. Once the nitrites spike starts to decline I increase the amount of ammonia at the end to whatever my target is, in your case, 4ppm. This usually only takes a few days. I increase the ammonia at the end to avoid the huge nitrite spike that comes from continually adding large amounts of ammonia when the bacteria colonies which consume the nitrites have not developed as much as the ones consuming the ammonia.
An alternative, but equally valid, approach is to dose back to 4ppm every day. The advantage to this approach is that there is no ramp period at the end of the cycle. The only problem is that if you do hit a nitrite spike, you are converting tons of ammonia to nitrite every day which then forces water changes.
For me, the long nitrite spike seems to only happen when I use ammonia directly. When using ammonia directly I see the ammonia get consumed fairly quickly and then nitrite hang around forever. In a fish-in cycle I usually see the opposite, the ammonia hanging around forever and then a brief spike in nitrites which quickly goes away.
Generally, the total amount of time is the same either way, 6-8 weeks. Since I am impatient, I usually cheat and use bacteria additives.