Jennifer Garner is ''happiest'' when she has a natural look.

The '13 Going On 30' star has opened up about her favorite makeup looks, but insisted she prefers to appear au-naturel and just wear a small amount of mascara and blusher on a day-to-day basis because she likes to see her ''own skin''.

Speaking to PEOPLE, she said: ''I'm the happiest and most comfortable when I just look like myself. I'll use something on my lids that's all I need. The less make-up I have to wear, and the more of my own skin that I can see, the happier I am.''

The 46-year-old actress - who has daughters Violet, 12, and Seraphina, nine, and six-year-old Samuel with ex-husband Ben Affleck - also opened up on the skincare lessons she has learned throughout her life.

Jennifer spent a lot of time sailing as a kid and subsequently her fair skin would always burn, so the 'Wonder Park' star makes sure to instill the importance of UV protection into her young children.

She added: ''My parents were sailors, so when I was a young girl, my sisters and I spent most of our time on a boat. We would just burn and then peel it off and then burn again and peel it off. I try everything I can to make sure anyone younger than me who knows: you're going to want to protect your skin.''

And Jennifer - who is a Neutrogena brand ambassador - explained that she stashes sunscreen ''everywhere'' in her home because it is such a staple part of her beauty regime and keeps your skin safe from the sun.

She continued: ''Keep sunscreen everywhere, and always apply more than you think you need. You just have to be a nerd about it, and get it done!''