Oily skin types tend to have larger pores that are visible to the naked eyes. Normal an dry skin have smaller pores in comparison. There is nothing you can do to physically change the size of your pores; but you can change the look of them to make them appear smaller than they are. The trick is to play around with your make up routine.
First and foremost you need to stop using soap on your skin and follow a proper Cleansing, Toning, Moisturizing routine. Use a cream based cleanser on your face and wipe it off with a cotton ball. This helps to eliminate all dirt and oils from your skin and you will be left with clean pores. After this, if necessary, then you may use a face wash or a foam cleanser on your skin. Use an astringent or toner on your skin to close the pores after you have wiped off the water from it. Lastly use a moisturizer specially made for oily skin. You need to follow this routine 3 times a day.
Exfoliating your skin twice week works well. The exfoliating cream helps to remove the dirt and oil from your skin while removing the dead skin cell. After exfoliating, your skin feels softer as the dead skin cells are no more on your face.
A steam job on your face regularly will help as well. Use a few drops of lavender oil in a bowl of boiling water and steam your face. You will feel extremely refreshed and your skin will benefit from the herbs as well as the steam will help to clean your pores. Use a face pack that will soak the oils from your skin and help to close the blocked or open pores. It is best to use a clay based face pack. Keep it on your face for 15 minutes and then wash it off. Use an astringent immediately after washing your face.