It is important to start tweens on their basic skin care routine before they have skin issues.
Starting from 10-12 years old to keep their face clean from dirt and sweat daily with a gentle light cleanser. Their basic skincare regime is cleansing, moisturising and sunscreen. Sun protection is very important and alongside using sunscreen, they should use full sun protection by wearing a broad brim hat, sunglasses, staying in the shade when possible and wearing protective clothing such as SPF 50+ swimwear.
After washing their face and cleansing, they will need to pat dry their face with a clean face towel. Do not reuse the face towel, but place in the wash before reusing.
You can take it a step further and ensure they use one side of their pillow case one night, flip to the other side the next time and change the pillow case after that and continue this method.
Starting at this age will assist them to develop a healthy habit of skincare.