Definition: to recall or make an effort to keep a person, event or thing in one's mind.
Pronunciation (sign description): Dominant "10" hand (handshape) with the thumb in contact with the temple of the head and the palm facing left if right-handed (location and orienation) moves from the temple toward the non-dominant "10" handshape's thumb tip.
The sign REMEMBER originally came from KNOW+CONTINUE which became assimilated into one sign REMEMBER. Ref
First 100 words.
As you feel more comfortable with the first few hundreds of ASL signs, progress further with your vocabulary and learn signing more.