Clothing that is secure around the ankles and wrists is helpful. These are additional benefits from wearing appropriate clothing. You'll be providing a cushion against abrasions and protection from brambles and brush. And yes, you'll minimize your encounters with poison ivy. Apply repellents to your skin and to clothing.
Ticks are very resistant to insecticides, but there are effective repellents on the market.
Some of them are put directly on the skin. Socks and pant legs are important places to treat since they provide easy access to ticks. Since pets and livestock are also convenient hosts for ticks, treat them often and prevent tick infestation. Not only will your animals be more comfortable and healthy, but they will bring fewer ticks directly to you, thus minimizing your exposure. You'll be lowering the tick population in the general vicinity, and indirectly reducing your own tick exposure.