Modeling & Acne
That being said, it is completely okay to have a pimple every now and then. Heck, whenever I have a beauty shoot in particular, I'll always wake up that morning with one lone pimple somewhere on my forehead where it can't be hidden--go figure (thank my stars for Photoshop)! But there is a big difference between a pimple or two and a full-on acne breakout.
For those that are aspiring models with acne, I would suggest taking care of your skin first and getting your skin condition under control before attending any open casting calls or moving forward with getting your foot in the industry. Agencies won't look twice if your complexion is not up to par and because they prefer to have you show up with little to no makeup you can't count on tons of concealer and foundation to get you by. In a sense, that could be considered "false advertisement," if you get my meaning. Whether it's meeting with your agent or going to a casting, you will be required more often than not to show up with a clean face and no makeup. If you can't manage to pull this off successfully, it will be in your best interest to handle your skin care first and then pursue modeling. One thing at a time.
If you really want to get serious about kicking your acne so you can model, I would suggest visiting a good dermatologist and finding out whether you have mild, moderate or severe acne. I will say, however, that if your acne is severe with no chance of clearing up any time soon, modeling won't be in your future, unfortunately. Mild acne sufferers have a better shot at clearing up their condition, while moderate is definitely in between.
One of the best ways to get your complexion under control, in addition to using acne formulated skin care products, is to make water your best friend. Cut out the caffeine--coffee, soda, fruit juices with tons of fructose corn syrup and not much actual fruit juice, etc. Eliminate excessive sugar as well. Beef up on fresh fruits and veggies and substitute them for unhealthy snacks. Give it time as well. Acne doesn't go away overnight. A good skin care regimen combined with the right eating habits and enough time will result in skin that is more suitable for modeling.
I do want to also mention that you should actually be diagnosed with acne before using any acne formulated skin care products. Just because you have an occasional breakout every once in a while does not necessarily mean that you have acne. Products that are made for acne prone skin contain very harsh and strong chemicals that work fine for complexions with acne but can do major damage if you do not have this skin type. I cannot stress this enough. Instead of using acne products as a shortcut to take care of your occasional blemishes, simply be more diligent about your skin care routine--and if you don't currently have a skin care routine, shame on you and get one started now! Trust me, it will come in handy in the long run.
Photoshop is great but it should not be the main method for making a model look flawless. Already possessing a good and healthy complexion puts you far ahead of the competition and will increase your chances of booking a gig.