One thread might alternate function generators, another calculators, another accelerometers, another thermocouples, and so on. Always try to keep all threads active all the time. Clearly identify exactly what it is you are selling. Warts and all. Always point out one or more minor defects.
Obvious suggestions are to communicate often, to close quickly, clean thoroughly, pack well.
Make absolutely sure their thing works before it goes out the door. Give more than the others with useful tutorials or data links. Offer very low opening prices on proven items that seem certain to sell well. Avoid using reserves. Especially on stuff that seems like it will never move otherwise.