I routinely carry IWB, and I had the same fears as you. I still wear the same size pants, and I've found the spot that is most comfortable to carry. Any kind of carry feels weird at first, but then it feels like an extension of your body. I don't mind carrying at all now. I use a High Noon holster and love it.
Remember, the key is finding where you carry most comfortably. IWB gives you 360 degrees of options. Some like appendix carry. Some like right or left hip. Some like carrying in the small of the back so that the body's natural curvature conceals the gun more. All of these have advantages and disadvantages. SOB carry is uncomfortable when you sit down and lean back against a seat. Appendix carry can have the same problems if the barrel is long. Hip carry looks more asymmetric and may be slightly harder to conceal.
Find a holster you like. Buy it. Then start carrying, and you'll quickly figure out what works and doesn't work for you.
Remember, the key is finding where you carry most comfortably. IWB gives you 360 degrees of options. Some like appendix carry. Some like right or left hip. Some like carrying in the small of the back so that the body's natural curvature conceals the gun more. All of these have advantages and disadvantages. SOB carry is uncomfortable when you sit down and lean back against a seat. Appendix carry can have the same problems if the barrel is long. Hip carry looks more asymmetric and may be slightly harder to conceal.
Find a holster you like. Buy it. Then start carrying, and you'll quickly figure out what works and doesn't work for you.