Haha there are SOOO many topics on how to apply this one foundation! It's crazy! But I totally understand. So here's a repost of my method from another topic on here.
Here's my complete method (and I've gotten compliments on how perfect and natural my skin has looked, which has never happened before):
1.) Moisturise (or sunblock). Seriously. I have the oiliest skin in the world, but this is still an important step. I just use a light, oil-free one. Let this absorb for 5-10 minutes, then blot excess moisture with a tissue.
2.)Primer. I just use Monistat Chafing Gel. Works just as well, if not better than SPFP. However, because this is just dimethicone, it does not have any moisturizing ingredients in it. If you use a "real" primer, check to make sure the only main ingredients are silicone variants. If it has any moisturizers in it, skin Step 1, as you'll just be doubling up, wasting product, and adding another layer of product, which will just cause your makeup to slip. Let this set for one minute.
3.) Concealer. I dot a bit of a cream stick concealer on any red spots left from my finally receding (yay!) acne. Anything not too egregious can be left unconcealed (even discolorations and minor blemishes. My spots are like, fire engine red, so...) Let this set for one minute.
4.) Application. For a full face, I pour about a quarter size amount of the foundation onto a palette (if mixing with like, a strobe cream type product), or the back of my hand. Taking my Sephora Brand Professionnel Platinum Air Brush #55 (my HG brush, btw. And believe me, I've been through more than 20 foundation brushes, from $10 drugstore ones to $85 designer ones, both stippling and paddle), I spritz it with a setting spray (I prefer Cinema Secrets, but something like Fix+ would work fine), and I dip it in the product, and apply liberal dots all around my face. One dot on each apple of my cheeks, one each on the lower outer jawline, one on my chin, one on my forehead. These are pretty big, product-y dots, not little sheer pinpricks. Next I pick up the last of the product left on my palette/hand, and SWIPE it down my nose, under each eye, on the outer forehead region, and above my lips. Now we're getting there. Using the same brush, I begin stippling. NEVER buffing. Literally, starting at each cheek, and working outwards and downwards, I stipple quickly and in tight little motions until each side of my face is covered, stipple under and then over the eyes, then I move to the center. Before the next obvious step, I buff the brush lightly over each ear, around the hairline, and down the jawline onto my neck. Next, keep stippling the face. The product at this point should still look wet, but you'll start to feel a little resistance from it. This is good. Literally, just keep stippling all over (at this point, it doesn't matter where you start and end. I usually sit down and watch some TV, or read while I'm doing this step, as I usually do it for a good 2-3 minutes, though a minute at least should be fine). When you're done, it should still look very slightly damp, but not LOOK sticky (although it should feel this way). Let it set for 3-5 minutes (this is the most important step).
5.) Powder. I use Kett Sett Powder (used in airbrush makeup and undetectable to the naked eye, and HD cameras, but any finely milled loose powder should be acceptable). Taking my MAKE UP FOR EVER HD Kabuki Brush (my other HG powder brush) (although any soft, not too dense kabuki brush should work. Just don't use a regular powder brush, or it won't stick, and not a puff, as you'll get a mask-y look), I buff a very light amount all over my face, starting from the center and working outwards and downwards, making sure to apply only the SLIGHTEST amount of pressure. Just keep buffing (lightly) even after you can't see the powder any more, as this will really set the foundation and keep it oil free.
6.) Extras. Apply bronzer or blush, etc. I rebuff a bit of MUFE HD Microfinish Powder (using the same brush) over afterwards just to help blend and set it in.
7.) Set. Spritz my face with a lil MUFE Mist & Fix. Don't touch your face for at least 3 minutes after this.
Sorry for the huge explanation, but I felt that if I was gonna go through it, might as well be thorough. Even though it seems to take a long time, not including moisturizing and priming, my whole routine takes only 10-15 minutes, and can be done in about 5 if I'm in a huge hurry (skipping concealer, stippling less, less powder buffing, etc.). Of course, my routine doesn't involve eyeshadow, so...
Final thoughts: Please, please, please, don't use your fingers, or a sponge for this foundation. I have not found a single way to make it work with these methods to get a realistic, natural finish (if you need full coverage). Sponges work fine (dampened) for a sheerer finish, or dry for like, theatrics, but not day to day wear. If you have a choice, use a dense stippling brush over a duo fibre brush, and a duo fibre brush over a paddle brush. And don't be discouraged if it doesn't look right for the first week. My skin, and my application, took about a week of getting used to it, and now, it works, and looks better than the $100 foundations I used to purchase. Good luck!
