In addition to official classification and identification shown by @Gkikas-LGPZ, I use the way how clouds are named to identify them. But being named by Latin words their meaning is not obvious for everyone. To identify the 10 main cloud types, you must remember 5 Latin words:

Cirrus: means tuft of hair. Used for high level clouds looking to hairs. As a prefix this word is used for all clouds at high level.
Alto: means in altitude. Used for mid level clouds.
Stratus: means layer. Used for the shape of stratiform clouds.
Cumulus: means heap. Used for the shape of cumuliform clouds.
Nimbus: means rain cloud.

So the cloud names come from their altitude and their shape and they can be summarised in this table and this picture:


From the 10 types shown above, 2 are missing in the table.
Cirrus, easy to identify by their shape and altitude.
Stratocumulus which is a hybrid of stratus and cumulus.

Note that cumulus can extend up to mid levels. This table is of course a simplification to remember cloud names.
Shapes are not difficult to identify, but altitude is not so easy.