Interface XBEE with Arduino without shield

Some of the points which needs to be taken care of while interfacing XBEE with arduino are:

• XBEE operates at 3.3V logic.
• 3.3V supply on most of the Arduinos are not capable of supplying enough current to XBEE.

Solution to logic level problem is you can convert logic level of arduino at 5V to 3.3V.
For example in below schematic a n-channel mosfet(2n7000) is used to convert 5V logic of TX line of arduino to 3.3V. Converting 3.3V TX line of XBEE to 5V is not required as it's high and low signals are distinguishable on 5V input also.

For 3.3V supply you can convert 5V supply of arduino(5V Vcc of arduino is capable of supplying ~100mA current) into 3.3V using voltage regulator or use another power supply to fed 3.3V to xbee.

Below is complete breadboard diagram of how to interface XBEE with Arduino uno using 2n7000 n-channel mosfet and using LD1117 3.3V voltage regulator to supply 3.3V to XBEE.