dry means non-fertile cm. When the fluid is exposed to the air it should dry quickly and be the consistancy of spit from the inside of your cheek. Dry does not mean bone dry. Non-fertile cm is thin. Rub your fingers together. If it starts to dry like elmers glue that is an indication of returning fertility. What I mean is crumbly or rubbery. Also if you pull your fingers apart and there is a string like egg white this is fertile.
IMPORTANT: You have to read a book or take lessons because although the system is not complicated it is important that you get it right.
For now you can follow the rules of LAM. As long as you do not recieve a period, dd is ebf and bf on demand, she is not sleeping through the night(5 hours straight is sleeping through the night), and is less than six months old you can assume that you are safe to have sex without protection. As soon as any of these factors changes you must start charting and assume fertility.
I have also heard recently that light plays a factor. At night sleep in pitch black to keep your fertility from returning.