It is warm in Las Vegas in July. Please plan so you can be comfortable. All indoor places have great air-conditioning so you may need an extra layer. We will be outdoor a minimum time for day of wedding.
If you're an explorer that plans to walk everywhere, consider your footwear! I can't stress the warm temperature as well as there can be a lot of walking between Casinos. Dress light and wear comfortable shoes. All indoors areas are well air-conditioned so some layering might be needed. Anything goes clothing wise in Vegas from formal to very casual. That's part of the fun. No stress! I recommend planning on Taxis/Ubers to get around.
Please go to website. Highly recommended by Waldorf Astoria Las Vegas. https://nahusa.com