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There is a lot of info out there on carb tuning, so instead of going into writing a book on the subject, I can give you some basic and essential information to help.
First is to understand what jets will affect what part of the throttle opening.
In really simple terms...
Pilot jet: Affects the amount of fuel for the idle mixture as well as the throttle up to about 1/4 throttle, with the greatest effect up to 1/8th throttle.
The best way to determine if a pilot jet is too rich or too lean is by first setting the idle mixture. From lightly seated, if it takes less than 1 turn out on the mixture screw then the pilot jet is too large. If it takes more than 2 1/2 -3 turns out, this indicates that the pilot jet is too small. Ideally the mixture screw should be between 1 and 2 turns out to achieve a stable idle.
The second way to determine if a pilot jet is too lean or rich is how the bike acts when at very light constant throttle, say cruising down the street at maybe 25mph with the throttle just slightly opened. If it cuts in and out, hesistates, pops, etc, then you are likely too lean. If it feels like its just bogging out and losing power, it is likely too rich.
Needle and needle jet: This mainly affects the fueling between 1/4 and 3/4 throttle. Raising the needle with a lower clip position or shims will make this range of throttle richer, while lowering it with a higher clip makes it leaner. Since the needle mixture is also affected by the main jet size, it is usually best to tune the needle position last. Ideally the needle should be as close to its center clip as possible.
Main jet: This affects the throttle mainly from 3/4 throttle to wide open.
Some easy indicators for this when rolling to wide open throttle include:
If the bike hesistates for a second and then starts accelerating, then it is a good indicator of being too lean on the main jet. Go up a jet size.
If you roll on to wide open throttle and the bike boggs out, and may even cut out, it is too rich. Go down a jet size.
Once you get to a point where the bike does neither of these behaviors, then the best way to really determine if your main jet is appropriately sized is to do a plug chop on a fresh plug. A quick google search can bring up a lot of info on this.
Also keep in mind that all carb tuning should be done on an engine at operating temp (hot). This includes idle mixture.
The last thing to keep in mind is that even though each jet has the greatest effects at certain throttle positions, every jet still adds fuel, i.e. - If you increase the pilot jet size, it will add a tiny bit more fuel to the main jet as well. We are talking a very small level, around 10% of the total fueling at most, but it is something to keep in mind. If you set the idle mixture but then jump 2 main jet sizes, your idle may change a little and you will need to slightly adjust the mixture screw.
As far as jetting recommendations, what I would recommend is just a generic, and likely too rich setup to start with, but too rich is better than too lean. You will want to have a few sizes of each jet to really dial it in.
My recommendations still stand with a 30 pilot and a 115 or 117.5 main jet with the OHC motors. If you have an OHV motor like me I can give you far more precise jetting suggestions, because I have hands on experience with it, and I don't have an idea of how different, if any, the OHC engines are in terms of fueling.
I would say to buy a 25, 27.5, and 30 pilot. And have a 110, 115, and 120 mains, at minimum. If you feel like it, grab a 112.5 and 117.5 as well. With my bike, the 115 was a touch too lean, and the 120 was too rich, the 117.5 worked out the best for me - being just ever so slightly on the rich side, which is what I prefer with aircooled engines.
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