I am very new to audio production and simply would like to take the hissing out of my speech audio recording. I have installed the de ess plugin to audacity but have no idea what to set the thres, freq, and Hf to in order to get rid of the hissing

Does it allow you to tweak the parameters while listening to playback? If so, set it to loop over an 'ess' part of the audio, set the threshold to whatever has the most effect on the sound, and adjust the frequencies to try and find the best values.

this is the one I use


it's really easy to use, just turn up the Sense and Depth, and sweep the Tune knob until you hear it working. Then turn down the Depth or Sense knobs to taste; too much and it can turn 'S' into 'TH'.