Toiletries and Medical Supplies: You will want to wear sunscreen at Joshua Tree National Park. Even in the winter, you'll get a lot of sun in the desert. The last thing you want is to end up with a burn. Bring along the bottle so you can re-apply as the day goes on!
Luggage and bags:
I went on nine trails during my four days in Joshua Tree. For the short hikes all you really need is something to cary your water in - a waist pack or carry the bottle in your hands. For the longer trips, I took my day pack from LL Bean. It held my water, food, first aid kit, clothes that I peeled off, everthing that I needed. It also was extremely light, easy to wear.
Clothing/Shoes/Weather Gear: After my light weight hiking boots blistered my toes coming down Ryan Mountain, I put on my Merrill jungle mocs, which were the biggest surprise of the trip. They were so comfortable and never once iritated my blisters, especially in combination with my Smartwool socks. No smell or sting.
Toiletries and Medical Supplies: My little first aid kit was perfect for my blistered toes. Band-aids, Neosporin, tape - all needed. Lip balm and sun block also are a must. No matter what you put on your face, you will still get some sun.
Photo Equipment: I have a very lightwieght Cannon Eos. No polarizong lens, no need for flash.
Camping/Beach/Outdoor Gear: Wear a hat. It helps keep your head cool and the sun out of your eyes. Sunglasses, too.
Miscellaneous: Buy 'ON FOOT in Joshua Tree National Park' by Patty A. Furbush. It has everything you need to know about all of the hikes in the park. I used it every single day, and whenever I began to loose confidence about where I was during the hikes, the book helped reassure me that i was on the right path.