A great adventure and a thoroughly memorable experience. Great tour guide and surprisingly good food throughout. The trek itself was harder than expected, leave a couple days to acclimatize in Cusco.
In wet season hiking boots preferable to trainers, bring a head torch as it will likely be dark at some points while walking. Make sure and get a good poncho if there is a chance of rain, and unless confident in your ability to carry your luggage plus sleeping bag and roll mat then best to get help from a porter.
A great and memorable 4 days, met some amazing people. Would recommend.