What are things I should know before getting a breast augmentation?

Breast augmentation can be performed with a general anesthesia, so you'll sleep through the entire operation. Depending on the patient’s condition, the surgeon might use a local anesthesia, combined with a sedative to make him/her drowsy, the patient will be relaxed and awake, and may feel some discomfort.  
The types of incisions, the placement of the implant, the type of implant to be used, the size of the implant, will all depend on what the surgeon and the patient had agreed upon. The over-all success of the procedure however will depend on skills of the surgeon as well as how compliant the patient is in following his/her doctor’s orders.
 In any circumstance you should be prepared to feel pain. The intensity of the pain seems to be greater in a breast augmentation that involves an under-the-muscle procedure. Post-operative pain management is definitely an issue that you should discuss with your doctor BEFORE you have surgery.
On the first few days after the procedure, the patient will probably notice that the implant will look high and boxy. Moreover, the nipple placement may also seem “odd”. Don’t fret because with time the implant will soon settle, swells down, and the shape, texture, and overall appearance of the breasts will improve. 
Expect that the breasts will look “odd” for at least the first 2 to 6 weeks but it will significantly improve on the 3rd month after the procedure. 
Bruising is another possibility that you may experience. Ice packs seem to help reduce the severity of the bruising experienced as well as reducing the amount of pain and swelling that is experienced. 
Scars are inevitable even with the TUBA method. To improve the appearance of scars use topical treatments like Neosporin to help reduce infections, and Mederma to help reduce the raised portion of the scar. Ask your doctor for other suggestions for minimizing scars after the surgery. 
Stretch marks could also appear due to the sudden enlargement of the breasts. This however depends on your skin tone and the size of the implant.  
The total time for post-op recovery varies from person to person. Generally speaking, most doctors say that you should dramatically restrict the amount of physical activity you participate in during the first two weeks, and that you should be able to resume all of your normal physical activity after about four weeks.

The most important thing you should know before breast augmentation surgery is what type of implants will be used and why. You are implanting something foeign into your body, you want to be sure that it is the very best as you want the very best and most natural appearance, and you certainly don't want any problems that may require further cost and surgery.
The Australian government goes to to extreme lengths to ensure that the implanst that they (eventually) allow to be used are safe. This cannot be said for implants overseas. Overseas standards are generally very low.
Make sure you know exactly what is being implanted into your body and do not accept second best.
When you are implanting something foreign into your body -  choose only  the very best, which is generally the dearest. Like everything in life - you get what you pay for…… 

Thanks for the question, its one that many people should ask themselves before embarking on a procedure. The short andwer is lots, doing your homework is very important for any surgical procedure. The basic headings are:

1)The method of augmentation

2)The Facility of augmentation

3)Your doctor and follow up

We have recenlty published chapter on this very topic in a comprehensive international plastic surgery textbook bringing together 130 of the world's best for the task.

Farhadieh RD & Farhadi J: Breast Augmentation, Plastic & Reconstructive Surgery: Approaches and Techniques, Wiley & Blackwell, 2015.

http://onlinelibrary.wiley.com/doi/10.1002/9781118655412.ch38/summary

Each of these basic headings have many other items of subheadings

1) Method of augmenation

Currently the accepted and most reliable method is an implant based approach. This is depsite the increaing popularity of fat transfers which for now can not be thought of mainstay treatments are more marketing ploys in my opinion. Here are some basics

a) All implants including saline ones have a silicone shell. 

b)The shell can be textured scilicone, smooth silicone, or polyurethane, each offering on long term studies different rates of capsular contractures, the least with the polyurethane and the most with smooth shells, 

c) The content: silicone Vs saline, the former is aesthetically better and the latter on studies in the 1990s and earely 2000s showed consistently less capsular contracture rates, although at least one draw back is their feel and rippling

d) The pocket: the subpectoral pocket is known to reduce capsular contracture rates,

e)Most common way to do this is through the an incision under the breast which is considered to be the safest way for long term capsular contractures.

2)Your Doctor:

A qualified plastics surgeon with subspecialist cosmetic training is the safest way to approach this. Plastic surgeons are trained through the Royal Australasian College of Surgeons over at least a total of 7 years and are awarded an FRACS(Plast) upon completion and successful passage of a final exam. The Royal College of Surgeons is the only body in Australia that is recognised for plastic surgery training. Beyond this basic training you should look into the background of your surgeon as to whether they have had any further subspecialist training in the area of your interest in the form of formal felloshwips. Once you are happy with their expertise you need to make sure that you are a happy fit as this interpersonal relationship is the corner stone of your successful journey. 

3)The Facilities:

Finally, the facilities in which this takes place is important. In trimming costs for profit many cases are done under sedation or day procedure centers which in my opinion is a short cut not worth taking. The cost of your surgery in many respects reflects all of the above. But you should remember that its your body and any surgery is intended to be a permanant change. Its not a clothing item or car that can be bought at a budget and if you don't like it you would discard it.

I hope this helps as a starting point. 

You can find more details about breast procedures and implants on my website. 

http://www.panthea.com.au/breast-surgery/breast-augmentation/