Sampling and Tasting Red Wine

The important things to note when sampling a wine are: the appearance of the wine, smelling, tasting the wine. 

Appearance

To begin, with appearance you are looking at the wine for its colour.  It is best to hold your glass against a white background so you can obtain some contrast.  When looking at colours, just try to judge what colour the wine is.  Over time you will get better and better at this but for now use the following colours as a guide: Purple, Ruby Red, Deep Red, Red Brown, Mahogany, and Brown.

Smell

You must swirl the wine in your glass to aerate the wine.  Really stick your nose into the glass and really smell the wine.  The important thing here is to the smell of the wine leaves you with, i.e., e.g. fruit - strawberries, passion fruity, etc.; whether it tastes earthy, whether it is intense in smell, or light in smell.

Taste

Finally tasting:  take a sip of wine, purse your lips, and take in some air over your tongue and swish the wine in your mouth like a chewing motion.  Things to look for when describing taste.  Sweetness, acidity, tannin, body and flavours.  Other items are balance, length, depth, complexity, and typicity.

Sweetness is the opposite of being dry.  In other words, a very dry wine would not taste sweet at all.  While a semi sweet wine would be somewhere between a dry wine and sweet wine.  This is something you'll get better at with practice. 

Acidity is something that can be a factor in both red and white wines, but it is more prominent among white wines. Nevertheless it's a term should be familiar with.  Acidity comes from high levels of tartaric acid (wine also contains malic, citric and trace amounts of other acids), found in both red and white wine but much at a much higher level in white wines. 

Tannin is something you would detect if after you take a drink of red wine your mouth your mouth feels dry.  Acidity could have the same effect but if the wine is acidic you would start to salivate as your body tries to balance the ph of your saliva.  Tea also contains tannin (tannic acid).  If you have ever had a cup of strong tea you have certainly experienced tannin.

Body - Wines are typically classified as being light-bodied, medium bodied, or full bodied.  To judge whether a wine is medium, light, or full bodied you must take a sip of the wine, hold it in your mouth and you see how concentrated the wine seems, i.e. does it seem light, heavy or somewhere in between.  Certainly there is considerable level of subjectivity here but over time you will get better at this. 

Flavours - Flavour refers to the taste groupings such as: earthy, spicy and herbal.  Earthy examples would be mushrooms, leaves.  Spicy would be cloves, pepper etc.  Herbal would be mint, rosemary, etc.

Balance - Balance is the relationship between the tannin, sweetness, acidity, and alcohol in the wine.  In a balanced wine none of these aspects of taste would stick out or overwhelm the other.  As is the case with all aspects of describing red wine, determining whether it's balanced or not comes with practice.
 
Length - Different areas of the tongue and mouth detect different aspects of taste, i.e. sweetness, tannins, etc.  A wine that has good length would leave an impression on all areas.

Depth - A subjective term used to describe wine.  A wine with good depth would not taste flat, for instance.

Complexity - A wine that has many aspects of taste that keep coming out as you are sampling the wine. 
 
Typicity - This is indeed something that comes with experience and practice.  In order to tell whether a wine is a certain typicity you would be judging whether it fits the certain taste criteria, according to the type of grape it is made from, the specific wine region it comes from.