This trope implies a girl experiencing liquid gushing from her pussy while being sexually stimulated for the first time. She is surprized of what her body just did and it raises questions. Notably: is it pee ?; what just did happen ?; can I do it again?. Depending on the story and characters, the feelings can be mixed, between self-conciousness (i just wet the sheets) and pride (being able to release the pleasure). Make sure to write about the surprize and make it easy to understand that it was the first time. Make sure that the girl shows a lot of pleasure while it happens. The squirting can be of different intensities. The first squirt, and if it then followed by other squirts in the story does NOT represent huge amount nor a too powerful stream of liquid. Use a clear vocabulary to describe the liquid erupting, the feel of droplets against the skin and give details about the wetness of the pussy, before it happens. You can give visual cues of the aftermath of it. Take your time on this action by using more than one sentence.