In Japan, sometimes the way an item is wrapped and presented is just as important, if not more important, than the gift itself.
It is for this reason that a person will go to great lengths to buy a generic-looking garment from a high-end department store. The expense and trouble gone through to get the item, presented in a box, wrapped by the department store associates with their specially-marked packaging, shows that the person cares about the gift and the person receiving it. In the end, the point is not necessarily the gift itself (although you'd do well to think about the recipient's potential wants and needs). The point is the act of giving, and giving well.
Once you've decided on what to give, decide on how to wrap it. There are plenty of ways to do this, depending on the gift and circumstance. Between close friends, wrapping birthday gifts or holiday gifts American-style in gift paper with a bow might be acceptable. For other small gifts, in boxes, wrapped the way a professional at a department store is a good idea. For monetary gifts, many kinds of envelopes specifically for this kind of gift are available at any konbini- just be sure what kind you're getting! Those designs on the front mean something! If in doubt, ask which one is best. For other types of gifts, or for more formal occasions, furoshiki are indispensable. Furoshiki are traditional 'wrapping paper'; made of various fabrics, everything from cotton to silks, they come in all sizes and formality levels, and can be tied hundreds of ways to beautifully wrap your gift. And, since the furoshiki can be reused for years, they are very environmentally friends (when made of natural materials)- a major plus! The 'safest' colours are pastels or muted colours such as tan or navy.
If a gift is large or heavy, find a way to have it delivered to the person's home, so that they do not have to worry about the burden of transportation. Causing a person to carry something bulky or heavy onto a packed train is not exactly the definition of generosity.
Gifts should probably be carried in some form of shopping bag to be more inconspicuous. If giving many gifts to a group, make sure everyone is present at once. If in a group and giving to one person, get that person alone to present the gift. Usually, gifts may be exchanged towards the end of an engagement.
Don't worry if no one opens your gifts immediately; this is done in politeness. That way, if one person's gift isn't received as well as anothers', there is no comparison, and no one feels let down, devalued, or left out. If someone ends up not using or liking your gift (perhaps you gave a specialty food they have an allergy to), you do not see their disappointment, and neither of you lose face. You should follow suit, and thank the giver. When you present your gift, make sure to offer it with both hands and a bow appropriate to the situation. A useful phrase is "Tsumaranai mon desu," meaning "It's an uninteresting thing..." This shows humility and presents the idea that your relationship is more important than even the most expensive and extravagant gift. If you are offered a gift, it is polite to refuse once or twice. This sends the message that you are not associating with the person only to acquire their resources.
Take heart! All this seems complicated now, but really, it's just as complicated as the gift-giving process in America to outsiders. Don't worry too much. Just do your best, and when in doubt, try to ask someone who understands the particular situation. Foreigners are not expected to be perfect, but just like when someone is a foreigner here, it is always appreciated when a person tries to do the 'right' thing. It shows that you care!
Next: The Cultural Importance of Rice