As updos look good mostly with short and medium hair, they may not seem appropriate in case you have long hair. Since they create volume over or behind the head, if long hair is used for making an updo, the style will look inappropriate according to the size of the face.
As with regards to shorter or medium hair, the volume will be created appropriately when the hair is styled over or at the back.
Unlike short hair, there are many variations that can be made with updos on medium hair. To make these variations and patterns, you will have to use more hair accessories. If you have medium hair, you can experiment with updos with bangs. Medium hair updos really look good with straight and long bangs. A bun is also a good option for medium-length hair.
You can even take some of the front hair and style them as fringes. A somewhat intricate style would be to make a French braid and turn it around along with the updo. For curly hair, you just have to place all the curls over the head to make a nice pattern.
Styling cute updos is just a matter of setting hair on or behind the head in a manner you prefer. Therefore, you can do variations to the hair patterns with hair accessories. Use a good hairspray to keep your hair in place. Also, remember to condition your hair before trying out any style, so that your hair do not get damaged due to the clips and pins used.