There are a lot of factors on how a Pokemon spawns in Pokemon Go. There is an article that tackles where to find each Pokemon type's spawn points.
Another method is by studying the nest types, here you will learn how to identify Pokemon nests and from there you will decide to stay on that spot or move on to another nest, depending on what Pokemon you are looking for.
There is also an experiment on how to increase the number of times a Pokemon spawns in your very own home. The method requires multiple accounts - be careful with this one, and a bunch of mobile devices.
In this article, however, we will teach you how to make the most out of 1 incense. Technically it will spawn a maximum of 30 to 36 Pokemon, under its effect alone, and not counting the common spawns that you will get without the incense.
Incense effect, technicalities
An incense supposedly spawns a Pokemon every 5 minutes - if you stay on one spot. If you decide to walk around an urban area, it can increase up to 15 pokemon per 1 incense session (an incense lasts for 30 minutes in case you forgot.)
Below is the source code that runs the incense feature:
What we can decipher is:
IncenseLifeTimeSeconds:1800 = the total Incense effectivity time is 30 Minutes
StandingTimeBetweenEncounterSec:300 = detects if you stay at the same gps location, 1 Pokemon spawns every 300 seconds (5 mins)
MovingTimeBetweenEncounterSec:60 = setting the time to walk 200 Meters (explained on next line)
DistanceRequiredForShorterIntervalMeters:200 = if you walk 200 meters within 60 seconds the spawn rate will increase by 1
What this tells us is that everytime you use an Incense in Pokemon Go, it will give you 30 minutes of effectivity, detects your walking distance, gives you a window of 60 seconds to reach 200m, if you have walked 200 meters within 60 seconds, the spawn rate will increase by 1. If you count them altogether, you will have a total of 30 additional Pokemon spawned on top of the 6 (when not moving) within the 30 minute window of the incense. That's a posibility of 36 Pokemon spawned per minute.
To be able to achieve this though, you need to immediately move after activating the Incense. This also requires you to walk 200 meters per minute, that's 200 big steps per 60 seconds, so performing this technique is more of a jogging instead of walking while playing Pokemon Go. As always, be careful with where you are heading to.
Otaku Kart has claimed that they tried this method and got around 26 spawns with 1 incense. Good catch indeed! Let us know with your comments below if this has or hasn't worked for you.
If you like to know more about how Pokemon spawn works in Pokemon Go, here is a video that would explain it: