How do I design the characters of other planet species that people could tell their gender and personality and so on without my explanation?

Stick to the context of my previous work ( a new planet generated by a tiny green image ), the time has passed, on that planet, there comes an intelligent life form. So, we are going to create this intelligent life form on that planet. However, this story is telling to humans, therefore, we have to make the characters of this intelligent life can be read by humans. (those conditions is very important to show us the design direction of the character.)

Firstly, we have to study the human perception of male and female appearance.

The general human sexual feature might be the first starting point that comes out from your mind. Still, this is not suitable for this case.
Because if we create a character by highly referencing the general human feature, then the final appearance of the creature would be too close to the human that you might be seeing it as a mutant of human, but not an aliens species creatures.

Thus, we could start the study about how do humans relate another species to the perception of humans’ features. Perception always involved with emotions, such as relaxation and joy, or hate or disgust.
The most familiar and accessible instance would be the cat.

Why do humans love cats so much? Are there any features of cats link to some of the humans’ perceptions and evoke the relevant emotional response? Yes, the characteristics of the cat’s appearance highly related to the perception of Baby.

Secondary, where the human’s perception comes from. Humans built the perception by observation, of course. So, what is the main information resource for humans nowadays? Social media. Social media influence dramatically about aesthetics. It also means social media affects the perception of male and female features. This means in order to make people being sensitive to the gender of my character design that I have to make the characters more trendy on gender features. In short, I pick some images that could represent the body shape of male and female, the eyes form featuring male and female, and the different personalities of two genders. And I used those images to abstract some symbols to prepare for the character’s design.

Finally, turn to the image below, read them by order, it shows the process of my thoughts about how did I come up with the ideas.