I don’t know if it’s possible to ALWAYS feel attractive. I am sure that even supermodels have days when they feel like a zitty frumpy mess (or some variation thereof).
I think the best you can do is cultivate self-love (e.g. make a list every day of things you love about yourself and choose to appreciate aspects of your appearance that you like rather than actively hating aspects you don’t like), get clothing and makeup that makes you feel good, and “fake it til you make it.”