Selecting the right shade: Picking the right shade is CRUCIAL and really isn't as hard as some think. Swatch a little of the foundation right along your jawline. The foundation should disappear into your skin. There shouldn't be any visible lines where the makeup stops. It's really as easy as that. If you are shopping for a department store brand, there will be advisors to assist you with getting it right on the first go, but if you're shopping for drugstore brands, this can be a little more tricky. Most drugstores have great return policies on their cosmetics (Rite Aid and CVS to name a few. I think Walmart allows returns on cosmetics also). I would suggest purchasing a few shades at once if you can afford it and just return the ones that don't work. This would save you from running back to the store and exchanging one at a time.
Choosing the correct formula is definitely a matter of preference! There are so many to choose from so if you know your skin type, this will help you arrive at a decision more quickly. I will give my opinion on just a few of the formulas:
POWDER (PRESSED)- Powder foundation can be used for sheer to medium coverage. I don't like powder foundations because with my oily skin, it just tends to oxidize and turn orange on me. YUCK. If you only need light coverage, this may be a good way to go. I probably wouldn't use pressed powder foundation on dry skin as it can end up looking flaky in spots. Pressed powder foundation may be ideal for aging skin as it doesn't settle into fine lines as easily as liquid or creme formulas. Brands I like: Clinique
LIQUID: Liquid foundations are great for all types of coverage! Just be careful because if you have oily skin, you want to make sure you get an oil-free formula and if you're really dry, you will want to find a moisturizing formula. Liquid is versatile because it can be mixed in with moisturizer or sunscreen for a more sheer coverage, or you can mix multiple colors together for a custom shade! Make sure you purchase a setting/finishing powder if you go with liquid (see some information on finishing powders below) Brands I like: Make Up For Ever
CREME: Creme foundations are mostly used for professional applications (for theater, film and photography) because it offers really full and matte coverage. You can certainly buy creme foundation for everyday use but for some people it tends to be too heavy. A great benefit of creme foundation is you don't have to use a seperate concealer because the creme covers blemishes really well. Brands I like: Graftobian, Kryolan
My skin type is oily with large pores so when I buy foundation, I'm looking for something with medium to full coverage. To achieve that, my go-to foundation is Make Up For Ever's high def foundation in #170 (I guess that would be comparible to MAC NW35).
This foundation runs about $40USD at Sephora...expensive but worth every penny. I set this foundation with a very inexpensive loose powder in Translucent Honey by Cover Girl (about $6 at Walmart or Target) It only comes in about 4 or 5 shades so it's really easy to pick the correct color. To keep your foundation in place and reduce the amount of times you need to blot during the day, I highly recommend this finishing powder. Also, if you're oily, I recommend investing in a foundation primer to put on BEFORE your foundation goes on. This will help reduce the appearance of fine lines and large pores. It will also help your foundation to go on smoother.
In your purse, you should keep some blotting paper (I use Boscia Lavender Blotting Linens $10) and/or some blot powder to keep your foundation fresh all day. I have yet to find a foundation to keep me matte all day, but the primer and the loose powder allows me to go for hours before I need to touch up.
Hope this helps!