The Wine Council of Ontario produces Ontario Wine Guides/Wine Maps to help you navigate your way through wine country. Plan ahead of time, and decide which wineries you want to visit during your tour. The Wine Guide provides information about each winery, their hours of operation and tour times. If you are looking for a particular wine during your tour, research wineries and find out which varieties they are known for.
Designated Driver:
Before you head out on your wine tour, make sure that you have a designated driver. After a few wineries, the samples can add up to a lot of wine. If your whole groups wants to partake in tastings for your wine tour, look into hiring a driver or a tour bus. There are plenty of companies that will take you around wine country to various wineries. It is a safe and enjoyable way to taste your way through wine country.
Ask Questions:
No question is a silly question. If you have any questions about the wine you are tasting, or the winemaking process, ask. Winery staff are trained to educate guests, and provide you with an informative, and educational experience. If you want to know how wine is made, or what it takes to make grapes grow, just ask.
Sight, Smell, Taste:
When you are out wine touring, take some time to appreciate the wines you encounter. Use all of your senses including your sight, smell and taste. Use your eyes to look at the colour and clarity of the wine. Smell the wine and appreciate it's aroma. Lastly, taste the wine. Take a portion of your sample and swirl it around your mouth to cleanse the palate. It has been said to never judge a wine by the first sip. Take another couple of sips after your palate has been cleansed, and then you will be able to tell if you enjoy the taste of the wine.
Spitting is Okay:
You do not have to consume your entire sample. All wineries will provide spitoons which they generally will keep on their tasting bar. In the world of wine, spitting is the norm and entirely acceptable.
Dumping Wine:
You will generally receive a 1 oz. sample of wine. It is not necessary to finish your entire sample. Again, the spitoons are the place to dump any extra wine you do not want to consume.
Eat Along the Way:
It is always a great idea to have some food during your wine tour. Having some food will not only help to metabolize the wine you are consuming, but also will allow you to experience the local cunlinary scene. After you have visited a couple of wineries, take a break and then continue. While visiting wineries ask the staff if they have any suggestions for good places to eat in the area. Some wineries have restaurants on site as well.
Sensory Blockers:
Wine tasting is a sensory experience. Try not to chew any gum, or consume any strong liquids (such as coffee, tea, or soda) while you are out wine touring. These strong flavours will affect the wine you are tasting. Also, try not to wear perfumes, or any strong scents while you are wine touring. Strong scents will influence the aroma of the wine.
Take a Tour:
Various wineries offer public tours which allow you experience "behind the scenes" action at the winery. It is a great way to learn about the wine region you are visiting, the winery, as well as the winemaking process. Wineries will generally have their tour times on their website, or you can find them in the Ontario Wine Guide. Call the wineries to see if you can book ahead of time, or simply join the tour when you arrive on the day.
Purchase:
Most of the wines you taste will only be available to purchase at the winery. If you find a wine that you enjoy and are interested in purchasing, buy it. If you are an Ontario resident, some wineries have wine clubs which allow you to receive shipments of wine each month. Ask questions, and see what wines are sold solely at the winery.
Take it all in:
Take advantage of the peaceful vineyards, and the scenic beauty. Sit in a vineyard, amongst the grape vines, and take it all in. Their is nothing quite like a beautiful summer night, looking out towards the vineyards and enjoying the locally produced wine, and locally grown food.

Above all, have fun and enjoy your time in Ontario Wine Country. Cheers!