The website "Handspeak" uses two different colors to identify ASL and English: gloss in blue to indicate ASL and green in translation for English.
What is gloss? Wilcox describes gloss as follows:
Glossing is the practice of writing a morpheme-by-morpheme 'translation' using English words. Glosses indicate what the individual parts of the native word mean. Glosses do not provide a true translation, which would instead use appropriate English ways of saying "The same thing."
For example, German Es geht mir gut may be glossed as "It goes to-me good" (the hyphenated gloss "to-me" indicates that it refers to a single word in the original). A true English translation of this expression would be something like, "I'm doing fine."
Below is a list of some conventional and few modified symbols, their examples and explanation. The Handspeak site uses a video illustration whereever possible, so it uses less symbol details to reduce complexity.
capital letters. An English gloss in capital letters represents an ASL word or sign. It is known as gloss. Remember this is not a translation. It is only an approximate representation of the ASL sign itself, not necessarily a meaning.
The hyphen - is used to represent a single ASL word/sign when more than one English word is used in gloss. E.g. stare-at
The plus sign + is used for ASL compound words. Eg true+work for sure enough, mother+father for parents.
The plus sign ++ at the end of a gloss indicates a number of repetition of an ASL word. Eg again++ (signing "again" two more time) meaning "again and again". Another example, HELP+++ for "help many/several times" or "help from time to time" depending on the duration of the movement and spatial reference to convey different meanings.
t is a shortcut for "topicalization", usually with raised eyebrows.
fs- represents a fingerspelled word. Eg fs-alice
# represents a fingerspelled loan sign. Eg #all
ix, a shortcut for "index", is for a referential point in space. IX1 can mean one side and IX2 for another side of the signing space. It doesn't matter which side it is as long as you establish a spatial reference for a noun and you keep consistent with it in a sentence or paragraph until the subject is changed.
cl is a shortcut for "classifier" which can function as a "pronoun" or another form that represents an ASL noun and/or its verb predicate. It is used in a verb phrase as well as prepositional phrase.
loc is a shortcut for "locative", a part of the grammatical structure in ASL.
Baker-Shenk, Charlotte and Cokley, Dennis. "Transcription Symbols." American Sign Language: A Teacher's Resource Text on Grammar and Culture. pp 1-29.
 Wilcox and Wilcox. "American Sign Language". Handbook of Undergraduate Second Language Education. Edited by Rosenthal, Judith. P 120.