There is no best way to Conceal Carry, but there's a best way for you and your context. Everyone's situation is different and what may be "best" for you isn't best for someone else or vice versa. 

As a licensed gun owner, one of the most critical decisions you have to make is how you're going to carry your firearm on a daily basis. This decision can depend on a number of factors, including your comfort, clothing, the nature of your daily life, and more. 

So let's talk about what the typical ways to conceal carry are, and how they might be best for you...or possibly not. 

An inside-the-waistband or IWB holster slips inside your pants and attaches to your belt, so it's supported on your waist, and covered with a shirt. 

IWB carry is more or less the default, the most popular choice and for good reason. Concealment is relatively easy, access is relatively quick, and it's usually comfortable enough for most people to carry every day with an IWB holster. 

The downsides are that an IWB holster doesn't work very well with business dress, especially with a tucked-in shirt. While concealment is generally easier than carrying outside the waistband, it's not necessarily the easiest if you have a larger gun than you can easily conceal with your clothing. 

While covering the gun is easy, it can become uncovered in a hurry. If your shirt rides up an inch or two (which can easily happen if you reach overhead) you might display the pistol for all to see...which might get you fired. In some professions, it can get you blackballed from working in that field ever again. 

While it is the "default," it's not necessarily the best choice for everyone. 

OWB carry involves securing the holstered firearm to your belt so it rests outside your trousers but under your shirt with an OWB holster. 

However, OWB carry typically requires more effort to conceal successfully. You'll likely need a jacket or a longer, looser shirt to ensure the firearm isn't visible.

OWB carry is more comfortable and very efficient, but requires dressing around the gun and choosing the gun and holster around the clothing. It's all but incompatible with most office dress codes unless you wear suits full time and have very carefully selected the gun and holster. 

It's the most comfortable, but concealment is the most difficult, especially with typical clothing that most people wear to work. 

Wearing an ankle holster can certainly conceal a pistol. It's a great choice for desk/office workers who have to worry about a business casual/business professional dress code or otherwise doesn't/can't risk a waistband holster being discovered. 

The downsides are that ankle carry is less accessible when standing or moving. Firearm choice is also limited as compact to full-size pistols are a nonstarter when it comes to ankle carry. 

Pocket carry is a long-standing default option for carrying a concealed firearm going back more than a century. However, it's not necessarily as easy as one might think. 

Modern semi-auto striker-fired pistols are not an optimal choice for pocket carry, as they snag easily on the draw. Irresponsible gun owners have pocket carried modern pistols without a pocket holster, resulting in negligent/unintentional discharges, giving the practice (and responsible gun owners) a bad name in the process. 

Firearm choice is limited to subcompact/micro pistols. Compact revolvers (snubbies) are one of the best choices, though a pocket-sized semi-auto (while not necessarily optimal) can be viable as well. 

Wardrobe selection is also complicated, as you need enough pocket to A.) hold and conceal the gun and a pocket holster and B.) not bulge and imprint, showing everyone you have a gun in your pocket. Cargo pocket carry is a feasible alternative to carrying in the front pocket. 

However, the kind of pants that will let you pocket carry without concealment issues (i.e. very roomy pants, cargo pants) are not necessarily compatible with many office dress codes. 

As you can tell, there's no "best" way to conceal carry. They all come with complications that you have to navigate. 

It's more that you have to consider what the best way to conceal carry for you is, which you have to figure out for yourself. Balance what you do for a living with the clothes you typically wear every day and what your lifestyle generally is. 

For a lot of people, that might mean an IWB holster, possibly in the appendix position. For some people, such as those who work in retail, an IWB (and DEFINITELY an OWB) is all but a non-starter; ankle carry and pocket carry might be the only practicable choices. 

So...there's no real "best." There's "best for you."