I found these tips about slow cookers from All Recipes (http://allrecipes.com/howto/slow-cooking-is-good-cooking/)
I thought they were extremely informative and hopefully you will too!
Is Browning Better?
You don’t need to brown meat before cooking it in a slow cooker, but there are some advantages. If you sear it with a little oil in a hot skillet, the meat develops more complex flavors. Always brown ground beef or any ground meat before adding it to your slow cooker: otherwise, the meat will clump together and add lots of grease to the finished product.
Go Easy on the Juice
Because slow cookers work at low temperatures with lids on, there’s nowhere for the liquid to go, so it just collects on the lid and bastes the food. If you’re adapting your favorite recipes from the stovetop or oven to the slow cooker, decrease the amount of liquid you use.
Lightly Spice
Whole spices such as bay leaves, peppercorns, or cinnamon sticks will give slow cooker items a very intense flavor if left in the pot for the entire cooking time, so use them sparingly. Ground spices as well as fresh and dried herbs, on the other hand, can lose much of their flavor if allowed to simmer for several hours in the slow cooker. It’s better to add these items during the last two hours of cooking if you can manage it.
Sooner or Later
The slow cooker is one of the few cooking methods where you can cut the cooking time by turning up the temperature and still get great results. If something takes 10 hours on the “low” setting, you can safely cook it for 5 hours on the “high” setting with very similar results.