Why do you need to test a new recipe before you serve it to your guests? Won't you have to go to a lot of work twice? While this is true, the results of a new recipe gone wrong could be more catastrophic then the time that is invested in testing out the recipe in the first place. The good news is that it is very possible to get the quality you want without a lot of investment of your time in the weeks leading up to a dinner party or special event.
First, choose a recipe that has techniques and cooking methods that you are used to. If you plan to deep fry a turkey, but have never done this in the past, one of the worst things you can do is to try and do it the day of. There are just too many risk factors involved. Instead, a few weeks prior to the special event, make a special dinner for you and your family of fried turkey and let them help you with the problems. This will help you to test out the cooking method and to determine if the turkey is seasoned well, cooked properly and overall works out.
There are times when you do not have to make the same meal well in advance to practice your cooking technique. For example, if you will be slicing a turkey for the first time, and are worried about doing a good job, give yourself some practice on a few chickens prepared over the last few weeks. Your family is unlikely to mind pieces of chicken rather than slices while your guests will definitely want slices of turkey. Give yourself the opportunity to test them out.
In addition to these types of testing, perhaps the most important one comes in at the spice level. If you have no invested enough time in testing out the combination of spices in a dish, do so before you add them to the meal. Test out the dish for flavour, salt content and for overall good taste with the combination of spices that you have used. This definitely will provide you with a bit of a better level of respect since when the final dish hits their plate, it is perfect.
Invest a bit of extra time in testing your recipes. It will pay off with a great meal. Choose recipes you love and have experience with if you just can't make time for testing.