To shift the gears on a motorcycle there is something important you should learn from the service manual and that is just exactly how many gears your bike has. Most bikes have either 4 or 5 gears. Modern Sports Bikes have 6 gears.
First put the bike in neutral, it is half way in between 1st and 2nd gear. Squeeze the clutch ( found on left handle bar) before trying to shift. You will know you are in neutral if a green light is showing on your gauges or if the bike rolls freely with the clutch out. Once in neutral you can start the bike, but keep the clutch in. According to your bikes shift pattern (Standard or GP Shift) you then shift into 1st gear by pushing the shift pedal up or down. Slowly let out the clutch while simultaneously increasing your RPM's with the throttle. The bike should start moving forward and as it does, release the clutch completely, but stay on the throttle. Once the bike is moving you can roll on the throttle to increase speed. As your RPM's increase you will need to shift into a higher gear; to do this you will need to squeeze the clutch in again. Then according to your bikes shift pattern, go to the next highest gear. Now release the clutch and roll on the throttle. To down shift you squeeze the clutch and shift to the next lowest gear, release the clutch. Be sure to match your RPM's to the wheel speed on a downshift or your rear tire can lock up resulting in a skid or worse, a low-side.
There are currently two shift patterns on modern motorcycles, standard and gp. Standard shift is well...standard, it will be found on most motorcyles. GP shift refers to the shift pattern used by professional racers. GP shift is reversed so that a rider does not have his foot under the shift pedal when needing to up-shift in a corner, it also makes for faster up-shifts. GP shift is primarily found on sports bikes and bikes intended for use on the track, but most sport bikes come with standard shift from the factory.
Shift patterns are set up as follows...
- Standard Shift (starting from neutral):
First gear is down 1
Neutral is up one and it is indicated by a green light on your bikes gauges. If you are not sure you are in Neutral ~ it is the only time when your bike will freely roll backwards when the clutch is not engaged.
Gears 2 ~ 4/5/6 are all up.
- GP or Reverse Shift (starting from neutral):
First gear is up 1
Neutral is down 1 and will likewise be indicated by a green light on your gauges.
Gear 2-6 are all down
Shifting gears on a motorcycle may seem awkward at first, but try it a few times in your garage or drive way with the bike off. Roll on the the throttle and practice using the clutch to shift up and down. If while riding you start going to fast or you feel as if you are not in control, pull in the clutch to disengage the engine from moving the rear wheel and apply brakes accordingly. Within a short time shifting through the gears will be second nature.
Ride Safe.
All good advise - but -
Firstly, and really, and I mean REALLY IMPORTANT thing to do before you even sit on your bike.
BOOK YOURSELF SOME TRAINING and use the training school bike to learn to ride in a safe environment.
Second important thing to do - GET SOME GOOD GEAR AND WEAR A HELMET. Your body, mother, father, wife, sister or brother will appreciate it

Thirdly, and this is important, PRACTICE, PRACTICE, PRACTICE in an empty car park.
I've been riding motorcycles for 30 years and I'm still learning. Changing gear is only one of the dark elements of riding bikes that you will have to learn, but don't worry, you will learn quickly.
Good luck and keep the rubberside down