To packing the bike properly, you have to know the steps about what we have to do for this action because if you have long journey but you don't pack your bike properly, it may your bike got errors in some parts, so the knowledge about how to pack the bike properly is needed.
The first step to pack the bike properly is preparing the bike box, it's easy to find the bike box. Local bike shop should have this so you will find any difficulty for the first step. But, find the bike box that your bike will fit in, so you have to know first about your bike size, and again this is not a difficult step.
Second step, reduce the tire pressure to make a proper packing of your bike; reduce the pressure properly, soft enough to receive the disruption from outside and it can be muted well.
The next step, remove the pedal to make it easier when packing the bike; when the pedals are removed, the bike will be easier to go to the bike box. Then, also remove the brake, mostly on front brake.
Then, the other parts that need to be remove are seatpost and the saddle, and also the handlebar and stem; yea, cockpit have to be removed when packing the bike into the bike box goodly. After all parts have been removed, you need to add cardboard, or something that can be the protection for the frame and fork.
Use the cardboard or something to cover the frame and fork so it can avoid the friction with another parts removed before. Then, the bike box has been waiting, so you need to place the bike into the box properly and the bike is ready to be shipped.