Learn the Spanish sign language alphabet, which will enable you to communicate in a rudimentary fashion with other signers. You will be able to spell your name to them and understand their name if they sign it to you. It will also get you more comfortable with using hand signals to communicate.
Learn Spanish sign language words. Once you have committed the alphabet to memory, you have probably begun to realize how long it would take to communicate if you had to spell everything out. Begin learning words in the order that they will be useful to you. Start with greetings and, if you are planning to use Spanish signing while traveling, focus on words you will use on your trip. If you will use Spanish sign language in your workplace, focus on business communication. If you are learning something relevant, it will be easier for you to remember it.
Expand your vocabulary gradually to build up the base of word that you know. Balance this by practice and review, to make sure that you retain the signs and phrases that you have already learned. Learning a new language takes a lot of time. Be patient and practice every day, and you may surprise yourself with your progress.
Practice communicating with anyone who wants to talk to you in Spanish sign language.