Before you try to figure out how to sell a car, you should first try to determine when is the right time to sell your car. Cars get a lot of wear and tear and you want to make sure you sell it before it starts falling apart. Once things start going seriously wrong with it, the value of your car drops and makes it very hard to get a good price.
Ask your mechanic what the condition is of your car and what you can expect in the future. He will be able to tell you what major things might go wrong and how much it will cost to repair them. You don't want to sell your car if you have just put $1000 to $2000 in repairs into it and if it needs those kind of repairs it will be hard to sell too.
Once a car passes the 100,000 mile mark it becomes harder to sell. That 100,000 miles is a sort of mental barrier that people have in their mind and makes a car seem old. After that amount of miles the parts in the car need to be changed more frequently as well.
Once you have decided when is the right time to sell your car, you will then have to figure out how to sell a car. There are many ways to get people interested in your car and that includes going online.
One of the things you can do is to ask your mechanic what to expect from your car (or truck) in the near future - he (she) should be able to tell you what kind of mechanical shape your car is in. You should mention any changes that you notice in the way your car runs - for example, a puff of blue smoke at startup or the transmission not engaging right away on a cold morning, or corrosion starting to appear here and there - these are the kind of early signs that could tell your mechanic about future problems with your car or truck.Another thing to remember is that it's more difficult to sell a car after a certain mileage or age (e.g. 100,000 miles).