You can tell a lot about a wine simply by looking at it, so give it a good once over. Is it clear and bright, or does it look a little murky or dull in color? Even if you're not a wine expert, your instincts will tell you if it looks appealing to drink. You'll also want to make sure the wine doesn't seem fizzy, like a glass of soda is when you first pour it. A few bubbles around the edges are normal, but if your glass of cabernet looks more like purple champagne, there's probably something wrong.
Check for clarity. Light passing through a wine with great clarity should make the wine look clear and sharp -- this even goes for red wines with a deep color. You shouldn't see any sediment or specks floating in your glass.
Next, inspect the color, which gives you the first hint of a wine's depth. A wine with good depth has a rich color and allows less light to pass through it. To get a good look at the true color of a wine, find a place with natural light and hold the glass up to a white background. Tip your glass to an angle of around 45 degrees to spread the wine out over the surface area, so you can see its range of colors.
The color of wine comes from the skin of the grape. Generally, white wines begin their lives with a pale hue and deepen with age to more of a caramel color. In contrast, young red wines start off purple or ruby, becoming paler with age and. Keep in mind that these are good guidelines to use, but know that the color of a wine can also vary depending on what techniques were used to make it. A darker wine isn't a sure sign of age. For example, whites that seem more golden have probably been aged in oak for a more full-bodied flavor, while wines with a green tint were probably made from grapes that were not fully ripe, creating a more acidic and tart wine. You wouldn't necessarily be able to tell that one is older than the other simply based on color, but don't let that stop you from making an educated guess. Becoming an expert in tasting wine is something that's learned through experience and observation.