Choosing specific shoes for salsa involves these qualities: lightweight, comfortable, flexible, made of real suede and/or leather, and have built-in extra cushioning in the sole. They need to give your foot more freedom of movement than regular shoes while keeping the heel "locked" in place. They have leather/suede soles to give you just the right amount of slip-and-grip on the dance floor while allowing your foot to pivot freely (to avoid knee damage). In general, any leather-soled or suede-soled shoes are "good" and rubber-soled sneakers, hiking boot, etc. are "not good".
The things to consider when choosing a salsa shoes are:
Heel sizes can be as low as 0.5" or as high as 4". The most common heel sizes are between 2"-3". Higher heels give more shape to the leg, but just that extra half an inch can cause a noticeable difference in how it feels to dance. For beginners, it is recommended to start with a 2.5" heel height
An open toe heel or strappy sandal is best for the Latin and Salsa dancing. This allows greater movement of the toes, which many dancers feel help with balance and creating a clean leg line.
Typically, your dance shoe size will be the same as your street shoe size. If your foot is narrow, you should go down 1/2 a size. If your foot is wider you should go up 1/2 a size from your regular street shoe. Remember, you want them to be snug, but not painful.
Choose the right strap: X-Strap (around arch) Great for newer dancers, this strap style anchors your foot to the arch of the shoe, providing an ideal amount of support and stability. If you are prone to "roll" your ankle in heels with a traditional ankle strap, you'll love the security this cross-strap will provide you.
The shoes that I recommend: