If your tie is wrinkled, but not too badly it is best to simply hang the tie from a hanger untied for a period of time. The longer this is done, the more effective it will be. Usually the weight of the tie will straighten it out and most of the wrinkles will be gone within a short time.
More Serious Wrinkles
If you have wrinkles too prominent to hang, you will need to roll up the tie from small end to large as tightly as possible. This will stretch the wrinkles while keeping the tie in the best position possible. This can be very effective depending on the type of material that is used in the tie. It is a good idea to use this method when packing your ties for a long trip.
The best way of keeping wrinkles a far and forgotten memory is to always untie ties after wearing them and rolling them tightly. Store them in this manner and it will help immensely.
If these methods fail to give the desired results then you can always use a nice steam iron to get the wrinkles out of your ties. Remember to use mild heat when ironing ties as it all depends on the type of material your ties are made from. Use a steam iron for best results as this helps penetrate the material and get the stubborn wrinkles out of your ties. Even if you are travelling you can always get a small iron from the hotel that you are staying at and simply iron your ties.
You can give all your wrinkled up ties to your nearest dry cleaner and they will definitely get then straightened and clean as well. A dry cleaner can remove even the most stubborn wrinkles as they have all the professional cleaning and ironing equipment on hand.