Live music production, mixing and remixing is done in a similar fashion to non-live music production. The music skills needed are much the same. Most DJs will try to use a laptop as little as possible during a live set, which requires the use of mixing consoles, effects units, samplers, and in some cases the use of vinyl. These give the audience a much better experience of watching a “live” performance.
Again, there’s enough software out there that give users the tools to achieve great sounding live mixes. Some basic software is free, other higher end programs offer free trails before you buy the full version, and some mixing consoles will come with a free copy of a program to allow you to get started, so make sure you check this option out before parting with your cash. YouTube is the best tool for learning all parameters of any software and the physical consoles as well.