You can prepare and print noshi paper yourself. It is not considered rude simply because a store did not provide it.
The harder part is not printing the paper, but choosing the right form for the occasion. Noshi paper varies depending on the type and color of the mizuhiki cords, the way they are tied, the wording written at the top, and the name of the person giving the gift. A bow knot is commonly used for occasions that may happily happen more than once, such as childbirth or school admission, while a knot that is not meant to be untied is used for occasions such as weddings. For funerals and other mourning gifts, the wrapping paper generally does not include the decorative noshi symbol in the upper-right corner.
If you already know which type to use, there is nothing wrong with printing it at home and attaching it yourself. The person receiving the gift may not pay much attention to the quality of the paper or where it was printed. Finding a template, printing it, adding the name, and attaching it neatly all take time. That effort can be seen as part of the gift itself.
In practice, however, many people simply let the store handle it. At a department store or a shop that regularly sells gifts, you can say, “This is for an oseibo year-end gift” or “This is a wedding gift,” and the staff will usually choose the appropriate noshi and prepare it for you. In many cases, having the store do this does not add much, if anything, to the price.
That makes the store option very convenient. You do not have to research the correct mizuhiki or wording yourself, and there is less chance of making a mistake. It is easier, and you can expect it to be done properly. This practical advantage is one reason many people in Japan simply ask the shop to take care of the noshi when buying the gift.
So a home-printed noshi is not less polite or automatically inferior. If you know what you are doing, preparing it yourself is perfectly acceptable. But if you are already buying the gift from a store, having the staff do it is often the easiest way to avoid mistakes. The difference is less about etiquette or status than about whether you want to spend the time doing it yourself or prefer convenience and certainty.
