Connect the individual outputs of your mixer to the rear of the patchbay. A standard home-studio-sized patchbay will usually be a "48 point" patchbay with 24 inputs and outputs on the rear, and 24 inputs and outputs on the front. For instance, on an eight-channel mixer, you would connect outputs one through eight to inputs one through eight on the rear panel of the patchbay.
Connect the correlating outputs from the rear of the patchbay to inputs one through eight of your recorder.
Add any effects you wish to run your channels through to the remaining inputs of your patchbay. For instance, connect the output of a delay unit to input 9 on the rear panel of the patchbay, then run output 9 on the rear panel of the patchbay to the input of your reverb. For stereo effects, use two inputs and outputs of the patchbay for each unit.
Repeat step 3 with all other desired effects you wish to add to your effects chain.
Connect the top-row outputs on the front panel of the patchbay to the bottom-row inputs of the effects you wish to run your channels through. For instance, if you wish to run your vocals from channel one from your mixer through the delay you placed in input 9 of the patchbay, take the first top output from the front panel of the patchbay and connect it to the bottom input of pair 9 on the front panel of the patchbay.
Depending on how you are monitoring your system, you will now hear the delay affecting the vocal track coming from channel one of your mixing console.