Toners are not essential in your skincare routine, unless your skin is oily. Many Singaporeans believe that it can help to tighten or close pores, but this is NOT true.
It can also irritate your skin if you have eczema or sensitive skin.
Toner was actually invented in the first place because cleansers in the past used to leave a soapy film on your skin, and toner helped to remove it.
If your skin is oily, then toner can be used. I'd pick one that has salicylic or hydroxy acid to improve skin oiliness and skin tone.
If your skin is NOT oily, then I'd prefer for you to replace toners with Retin A/retinoic acid, as the latter can actually help to tighten pores, unlike toners.
Here's what a skincare routine will look like:
AM (in order): Cleanser, Vitamin C Serum/Antioxidants, Moisturiser, Sunscreen
PM (in order): Cleanser, Moisturiser, Retin A
