"Since" and "because" are not sufficient and necessary indicators, but they are important words to understand. They are generally used to introduce a premise, and knowing how they are used will help you with argument structure.
"I will likely not make it to the party on time, because there is a lot of traffic right now." Premise: There is a lot of traffic right now. Conclusion: I will likely not make it to the party on time.
"Since Johnny was disqualified from the tournament, Jimmy will probably win." Premise: Johnny was disqualified. Conclusion: Jimmy will probably win
As far as indicators that are not specifically mentioned in the sufficient and necessary lesson, I would keep an eye out for words that express necessity.
Requires Must be / Must have Needs Essential
Words like these often introduce necessary conditions. Other than that, just about all sufficient and necessary indicators can be found in the lesson or drills.
