The first time you look at an Open Cluster, you will describe it as: "Bunch of bright stars, spread across a big area." When you start to notice that some of the Open Clusters look different from other Open Clusters, it is time to start describing them more accurately. Answering these questions may help you.

1. Can this cluster be easily distinguished from the background stars?
2. What is the overall shape of the cluster?
3. How may stars can I count in the cluster?
4. Are the stars more concentrated in any one particular area?
5. Is this cluster resolved fully or is there some background nebulosity?
6. Is there any particular area in the cluster where you notice an absence of stars?
7. Are there any particularly bright stars in this cluster? If so, do they show colors?
8. Are the stars in the cluster all the same magnitude, or do they vary?
9. Are there any other deep-sky objects in the field. If so, what are their names?

What you don't see is also important in every description. "No field stars anywhere around this cluster" is a valid observation.