Finally got my ropes and started the JRD90 yesterday, did my maxes and already feeling the pain this morning... kind of scared of the challenge and I haven't even done D2 workout... any advice to get over the mental nerves and push through?

So I have been following the Jump Rope Dudes for a while and been watching their videos but today I finally joined and bought my jump ropes! Just have to wait for them to arrive to Perth, Australia then I can start my challenge! Any advice on incorporating jump rope into normal gym workout? Would you do it as a pre or post workout warmup/cool down?