Sometimes the て form has an adverbial meaning like: 重ねて or 歩いて行く and sometimes it functions as a way to connect two sentences. Is there an easy way to differentiate between what meaning is being used?
If there is a comma after the first verb in te-form, you're lucky, because it tends to be sequential actions ("V1 and V2", "V1, then V2"). The first verb can be a reason for the second verb.
- 朝起きて、顔を洗う。 (sequential actions)
- 彼女に会って、話をします。 (sequential actions)
- 電車が遅れて、遅刻した。 (sequential actions / reason)
If there is no comma, it can also refer to methods or surrounding events/situations, "V2 while V1" or "V2 by/with V1-ing". The correct meaning depends on the context.
- 急いで顔を洗う。 (situation)
- 歩いて学校に行く。 (method)
- 朝起きて顔を洗う。 (sequential actions)
"Context" may be a disappointing answer, but English also has many context-dependent words that confuses people who learn English as the second language. For example, "as he speaks" means both "while he speaks" and "because he speaks". "She must be a pro" means both "she has to be a pro" and "she is certainly a pro". You can soon get used to such ambiguous constructions once you've understood the possible meanings.