Lots of good advice above.
I carry lots of revolvers, from my LCR 22 up to my 4" 610.
I carry everything at 4 O'Clock. With a 2", and a 2-1/2" I can still access my billfold in my right back pocket.
When I go to a 3" revolver my billfold moves to my left front pocket.
I would go with a wood grip with smooth rounded edges on the butt end, and keep the size down. The butt is what will print with a 4" Square Butt.
Get a good holster. I carry everything in a Lobo Pancake. I have 8 of them for my assorted concealed carry handguns. Ray in my opinion makes the best holster for the money, and the Enhanced Pancake with Inner Hammer Shield is a very good concealed carry holster.
http://lobogunleather.com/
Next is a cover garment. I have fishing shirts like the Columbia line. I have several Woolrich Discrete Carry shirts I caught on sale for $20 each. I have a Dickie Kaki short sleeve shirt I wear unbuttoned over a Tee like a jacket. I have several Denum shirts I wear untucked. Also check out Duluth Trading Company
http://duluthtrading.com/ they have several long tail shirts to cure plumbers butt.
The 95587 is a pocket Tee with 3" extra tail length. It has a generous fit, and comes in something like 16 colors.
Longtail Henley short sleeve 67009 in 9 colors.
Duluth sells lots of things you will like. Even quality Edwin Jagger soap for your shaving mug. I price checked the shaving soap, and could not find a cheaper price anywhere on it.
As you carry, you will keep finding things that work. An example would be a long tail light weight nylon windbreaker. How about a Carhartt Jac Shirt? Once you start to carry you will know what to look for in clothing.
Bottom line, the 4" 19 will carry ok in a quality holster with a good 1.5" belt. Check the grips and make sure they do not grab the cover garment, or print seriously. You can get by with some printing with no problem. Most folks you are around are oblivious, just do not show leather.
Your 19 does have one advantage for concealed carry. While not being as concealable as a J Frame, It is
Very Shootable. If you need to put lead on target, you have the right tool to get it their accurately.
Bob