Basically, bi-amping requires a special type of speaker. It must allow the bass driver and the mid/high driver(s) to be separated. This is evidenced by looking at the back of the speaker in question. You will see TWO binding posts, one for the bass abd the other for the highs. These are joined by a either a metal strip or a wire of some sort.
To bi amp in a minimalist fashion, you must remove that strip/wite joining both sets of speaker terminals. Then. you take your preamp output and feed it to TWO power amps per channel. The outputs of these power amps is then fed to each separate sets of speaker inputs.
If all goes well and the gain of the amps is the same, the sound is improved but, bear in mind that you are at the mercy of the speaker's designers as to which speaker gets what.
Additionally, more control can be had by inserting an electronic crossover between the preamp and the power amps. This gives you greater control over the range sent to each speaker and the levels of each.