Although it is very easy for a user to cut out a piece of paper to write something on, it is always nice when a designer has created something less “boring”.
Tags can have a functional purpose or be just decorative. This will guide you as to the actual dimensions to use.
If you want to provide a tag that will allow the user to enter some information (like dates, locations, names, etc.), you would want it to be large enough to add text to it. A tag that is at least one inch (300px) by two inches (600px) is probably the smallest you would want to offer. There is just enough space to add a little bit of information on it.
If you want to add any type of decoration on the tag, you will need to make it large to leave enough room for the user to write.
Larger tags can be similar to “pocket cards”. They would come in the “standard” size of 1200×900 px (4×3). But you don’t have to use that size if you are not creating a kit specifically for “pocket scrapping”.
Although most tags will tend to be rectangular, you can also make them round or oval. Other fun shapes can also be used like a heart or a star. Sometimes, a shape will be particularly suitable to your theme, other times, you just want to use that shape.
One easy way to create a tag would be to use a preset shape. Some shapes are already available but you can create your own and export them as presets so you can use them again later. There is one tutorial HERE to create custom tag shapes. You can also use some shapes from ready-made supplies like on DigitalScrapbook.com HERE.
PLAIN OR DECORATED
There is always room for some plain basic tags that the user can customize. However, you also can be very creative and embellish those tags in many ways. You can have some patterns all over or around the edges. You can add some outlines, scalloped edges, grungy edges, stitchings, etc. You can also embellish the tag with ribbons, glitters, strings, and more.
If you want, you can add a knot or a string to attach it. If you do so, be careful in adding some inside shadows on the tag itself.