Until the beginning of 2020, from 1974 to 2017, sixteen interstellar radio messages were sent to hypothetical extraterrestrial civilizations. They were sent from different radio telescopes and had different contents. The METI (Messaging Extraterrestrial Intelligence) projects had different concepts, some of which seem highly controversial. Therefore, a short list of criteria for future METI projects is proposed. As an example, we suggest an interstellar message in the radio frequency range of

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... e electromagnetic spectrum that we call "Golden Wings of a Lemniscate" (GWL). The GWL project is a simple message from Earthlings about their intelligence and readiness for interstellar contact. The digital part of the message contains ten images of lemniscates. The right half of the lemniscate includes the Golden Ratio concept with graphical drawings; the left parts of the lemniscate remain empty for ET reply messages. The experience of developing new projects of interstellar messages, initiative or response, is valuable. In the process of this work, various aspects of METI will be in-