If nothing else please please please don't try and eliminate all pores. I know its sounds tempting but its really not a good look in real life.
Using a puff and power you are pressing powder into the pore to "fill it in". Its a very simple and easy method and very very old school.
DO NOT over matte the skin. I like matte skin but do not OVER MATTE otherwise you will risk it looking like a mask.
I have not added back any shimmer etc... in this tutorial but i recommend you do as you want the skin to look alive. Matte skin photographs beautifully but at the same time we need skin to look real.
I used MAC blot powder for this. Any pressed or loose powder will work just fine as will powder foundations (not mineral).
I hope you can see the difference. I used a VERY light coating of foundation to begin with. That is it. The pores by my eyebrows in the before and after are nearly completely gone and the ones in the centre of my forehead are much reduced.
BUT SKIN NEEDS TO BREATH! No. the skin does not breath. The lungs do. Its a myth. Sure its not good to clog up the skin - but i would be more concerned with the lotions, potions, primers, moisturisers, SPF, more primers etc... than i would be with powder. I've not yet had anyone breakouts from this method BUT everyones skin is different.
Some of the pore products on the market really do work, temporarily and are worth looking into. And Clinique do amazing ones:
PS - i am working on a foundation brush that will give the look of flawless, poreless (realistic!) looking skin. I have a prototype that i love but i'm in the early stages of getting it made! Wish me luck. I really am very proud of it.