Black Friday marks the start of the official holiday shopping season, but recent trends show consumers are getting a head start in their holiday shopping.

Consumers are starting gift shopping earlier in the year, even before Thanksgiving, and they're using less credit to pay for holiday gifts, said Anita Bhappu, associate professor from University of Arizona Retailing and Consumer Sciences.

"They're spread over several months, the cost of those items that they're purchasing and they're actually purchasing with real cash via debit card or cash payment as opposed to credit payment," Bhappu said.

Last year's sales showed modest gains, she said. This year a four percent increase in overall retail sales is projected. One factor in that prediction is the drop in gas prices, she explained.

"The average consumer will have more money to spend on other things other than gas," Bhappu said.

The average amount each person will spend this holiday season is expected to drop from $755 to $740, she said.