Use the included gradio demo to get simple predictions on images, see how it feels. Demo will automatically download pretrained weights from https://huggingface.co/Blackroot/Anime-Aesthetic-Predictor-Medium/tree/main for you to try. You can rip the inference code out of the gradio demo and use it in any python script or whatever, feel free. This model is likely very overfit on my aesthetic preferences, the idea with this is to reduce the amount of work required to prep datasets, so you likely want to tune it to your preferences instead. Additionally, this was only trained on anime images.
See the wiki, it's designed to be pretty easy. You do need a GPU to train. https://github.com/CoffeeVampir3/easy-aesthetic-predictor/wiki