Hi, from experience I can definately recommend getting your man to help. Aside from giving you a much needed break, your LO needs to learn to be put down by someone other than you. Otherwise you may have problems later on. If you are worried about him doing things differently, have a good chat about what to do, in what order and why.
Also, write down the order of things for him to stress the importance of being consistant for your LO.
Having a special routine before bed and naps is so important, that way your LO comes to know whats happening, and that its time for sleep. A good bedtime routine may be: bath, massage, story & cuddles, feed, then bed (all taking between 20-30 mins). A good nap routine should be shorter, so may just be a couple of those things, e.g. walk quietly with bub for 5-10mins, story & cuddles, into bed. I suggest getting your LO to sleep in the same plce for all sleeps, this way she will associate it with sleep. The way they differenciate between day & night is that during the day some awake time is encouraged, during the night you keep your activites to the bare minimum in dim lighting. Its important to make sure your LO is still awake when you put her into cot. I have given up shush/pat as it was driving me nuts and didnt seem to help much. Rather, i now sit in a chair beside the cot, stroking his face and head if he's crying (i stop once he stops crying), and calmly repeating his sleep phrase, "Sleepy time Sam, Sleepy time". This really works. It may take a bit of crying for the first few days, but this gets less and less. It now takes around 5 mins and he's asleep. This is great because it is teaching him to self-soothe, and has also meant long sleeps. I would begin now, dont wait till after your visiters have been and gone. This really works, and if you are consistant, your LO should be sleeping great before the visitors arrive. Good luck