Sign Language is a living thing. You learn the langauge as it is for yourself first. When you are able to communicate slowly in the beginning with other deaf, you will slowly be taught new words and letters etc. Over a time with deaf you will have developed your own language. The reason I say its a living language is when I speak with deaf sometimes we learn new words from each other or new signs until we both agree on something. Then we continue on with the conversation and go from there. Signed Galludet English was my first langauge. ASL did not come until 20 or so years later in my lifetime. That was 30 years ago so I use a combination of both. Its always a interesting situation at the Deaf Church but all in all we do well with what we have there among the people both deaf, HOH and Hearing in there.
At some point you will gain fluency. Then you will learn to sing with it, curse with it and when it's not possible or needed to be used in several situations in life with deaf. At some point after that you could try out in testing to see if you can be a interpreter. They are pretty solid and strict about that type of work, ESPECICALLY in child services, medical services and most importantly law enforcement and court in particular. You would have been licensed by then for a particular type of languages for the deaf. Its a journey. Not something to be learned today and run off full speed tomorrow. Its a fun language and very beautiful when applied just so among those who have understanding of it. If I can learn and use ASL for msyelf then anyone can. Lord knows you can teach a old dog how to speak in new ways.
Religious Interpreting is a very special form of sign. Its done in a certain form and flow. To imply spiritual presence of God, Jesus and so on. When you add songs and formal sermon lessons into it it can be quite the sight to enjoy in Church if someone is sufficiently skilled to convert all that into a visual language.
The greatest application of sign language is not just letters, numbers and words to make a sentance or say something. You are also using your body's space around you and front to back to imply time progression to the past or to the future and eventually be able to establish several locations during the converstation to mean specific things. For example I might talk about my brother on my left then my sister in front and combined that with the parents (Both) on the right of me in the space in front of body. By pointing to them and referring to past, present or future tenses you can build quite the story in a short time around all three and yourself. Its a lot going on. Especially if the other person builds a similar structure with their bodies and then proceeds to communicate emotionally with facial and body langauge to boot.
IF that makes you a little confused, don't be. Its straight forward. Speaking English or written English cannot compete with sign language applied just so.
You will buy one specific book. Its been in print over 50 years in updated form as the languages evolve. "Joy of Signing" and then go find deaf people or those with knowledge of that language to communicate with. At some point you can set the book aside and just communicate. And everything will evolve from there the rest of your life.
Most people when they learn a language they want to learn the good stuff. Sometimes that includes various situations in life that are not necessarily set in a book. There is a whole lot of discovery during your learning.
One major rule if anything in signs. You DO NOT use sign langauge when in gangland areas. You do NOT. If you are with another deaf and traveling through a known gang area, you take care of all of your talking BEFORE you go travel through. Stay quiet until out and in safe area again wherever that may be. Sometimes gang people who do not know anything at all about deaf will just shoot you on sight using it and that would be that.
I learned to remember the alphabet within a week, because of I tried to see the similarities between the Latin alphabet and the way the hands are formed to look similar to the letters.
I've drawn on the fingers to show you the resemblance between the fingers and the letters. The only one I think looks more different from the Latin letters are P, Q and X. But putting extra effort into remember three letters is easier than doing the same with 26 letters. The first words I practiced on spelling was my name and names to people I knew. When I got used to the way it looked, I started practicing spelling basic words like "food", "water" etc., before moving on more advanced words.
The more exposure you gets from other spelling and you doing it yourself, the better you will get. Try to practice with someone for a few minutes per day for a week and you would see quick improvement. You won't necessary get fluent in one week and be able to read fast spellers, but you may learn to remember the letters and fingerspell yourself - in a slower to medium pace. Fluency in spelling alone often takes more than a week, but variates from person to person.
Look up fingerspelling word searches. Or finger seeks. I give those to my students and it helped a ton of my classmates in high school. It won't speed up your fingerspelling, only time and practice can do that, but it will help your brain start to pick up words thrown at you faster. Plus who doesn't enjoy a good word search