I have always struggled with this exact problem - how does one convey exactly what the flavours are. The discovery of bannana in a Grants blend was something of a breakthrough moment for me.
My 2 top tips are:
1) Add a drop (just a drop) of spring water. This can help to lower the ABV hence reducing the covering natre of the alcohol as well as 'lift' some of the more subtle flavours.
2) Close your eyes. You may look a little silly when tasting in public but in denying yourself one of your senses you are able to focus more on the others i.e. no sight can help focus on taste.