What do you mean you can't put your credit card? You'll need to add a card to be able to bid. You can sometimes get calls without bidding but for someone new it's going to help a lot. It will cost you money for a week or two but once you get your business going it can be really good money.
When I was new I priced super low for a week or two (and made zero money, but on purpose to build up my business and get my listing seen) and placed bids to get calls. Be sure to set a limit on your bids. I would limit my bids to what I could afford, maybe $5 a day and bid up $.10 cents a click, depending on my placement. It gets you horrible cheap callers but it does get you seen. You won't keep those callers once you raise prices likely but it will get you some placement boost.
Then after the first week or two definitely raise your prices! Once you start getting calls regularly put the price up to at least $1.99. Once you get popular you may never have to pay for bidding again.
If you're in a situation where you cannot afford to work a couple weeks at a rock bottom price and pay to bid thern I'd price a bit low, maybe 99 cents to see if you can get some calls and put all of the below advice in place as soon as you can. (don't stay at 99 cents though! it's just to get you started and get you seen. Once you get placement your price should be at least 1.99 or 2.99).
