After you have had an operation you want to keep the the scar as steady as possible for at least a couple of weeks. This means you should cover it with a bandage but you should also allow the scar to "breath" as much as possible.
You should also avoid exercising and overall moving as long as possible. This can of course be tricky. The older you are the slower the scars usually heal, unfortunally.
After my last surgery I tried to remain very still and avoid stretching my scars for a long time but still some of them expanded
It looks like it's inevitable in some areas which are prone to stretching.
And as a general rule the thicker the skin the more visible the scar will be. From the neck up the skin is quite this and the scars will usually faint easily but e.g. thighs, chest and stomach have thick skin and they are also more mobile which is why these areas often have more distinguishable scarring.
For some reason I have a scar in front of my left thigh that hasn't faded eventhough I have applied different gels to it. It is the same age as the one in my right thigh which is located at the side of my thigh. This scar is almost invisible? Why they differ I'm puzzled?
There are a multitude of different kinds of gels and lotions to help minimize the scars. I've used Mederma and Emu oil.
But if you have bigger scars you might want to check out the Derma Roller with nano needles that stimulate the skin and other skin care products like the ScarAway Silicone. There are some examples of products in here