Offering Free Shipping Tips and tricks?

I had a customer tell me that other sites similar to my own, offer some form of Free Shipping.
is there any tips or tricks to offer this like my competitors do with out loosing profit?
i dont want to pad my prices.
I have noticed that All similar sites as my Own went by the same price list ( all our prices are the same), and it comes down to ,who can get it cheaper.
i have taken a percentage off the price to be Priced lower than my competitors.
Is this enough to not offer shipping?

I see that no one has responded to this particular post.
I'm not sure that you're thinking about the situation quite right.

Everything costs something to someone, so at some point free shipping eats at the profit margin, but some of that is about increasing sales because of the "reduced" cost or moving older product that just isn't selling as well. There's a lot that can go into why free shipping, why now, why always, etc... But ultimately I would say it should be something that can be done without costing you the ability to run your business. And it really should be a part of your business plan to consider how and when you will offer various discounts. That type of planning helps in determining when to advertise, what to advertise, etc... It's not exactly like one day you would go, oh look, I've got extra money, let's put on a sale....

Not sure that I've provided much in the way of tips and tricks, and maybe someone has some that haven't seen this post yet... It does seem to me though that in the penny crunch that the request is how do I get something for nothing?