Check your computer for available USB ports. If you do not have access to two USB ports, you will only be able to use one of your UCA202 interfaces. Connect your mixing console to the UCA202s using your RCA stereo cables. Plug the cables into the output ports on the mixing board and the input ports on the UCA 202s. This will allow audio recorded into the mixer to be transmitted directly to the interfaces.
Open the audio editing software you typically use and create new audio tracks. Your software should recognize the UCA202s as valid input devices. Assign each of these to an individual audio track by designating each device as the audio input method for the individual track.
Connect your instrument and microphones to your mixing board using your instrument and XLR cables. Instrument cables plug directly into the "line-in" port on your mixer. Each channel on the mixer should have its own designated "line-in" port. Plug the three-pronged XLR cable into your microphone and matching port on the mixing board. Avoid plugging your microphone into an XLR port assigned to a channel that is already hosting an instrument cable.
Test your completed setup by pressing "record" and performing on your connected instruments. If the appropriate channel assignments have been made, audio will be recorded directly into your digital audio workstation. Because the UCA202 is not designed to receive individual line-in or XLR inputs, the total output of your mixer will be recorded into each individual audio channel in your software. Unless you are using an alternate mixing board for your second UCA202 device, the recorded audio for the second interface should be identical to the first.