Some tips on molting is to keep the humidity around the proper level for the species (see the
dedicated caresheets) most are in the 50-55% area. This is done most easiest by using a sprayer set to mist, and watering the mantid habitat every 2 to 3 days if needed (depends on your environment and if your running a heater/AC/etc). In the winter I run a humidifier (the steam kind) to help as the central heat in my house dries humidity to about 20%.
As you have kids during the time you notice the mantid(s) are becoming slower, tell-tale-signs such as swollen wingbuds and such (or even molting itself) do not get the mantid out/move the habitat/ or anything to shake or move the mantid as it my fall. Once it has molted from it's old skin it will need 24 hours to properly dry for the new skin to harden. During that time do not feed or handle the mantid, after 24 hours though feed it as it will be hungry.
Another is to not have any low hanging sticks. As some mantids will molt much too low and become stuck in their old shell as they do not have enough room below to pull themselves out, or hang and dry.
For molting material most simply use screen mesh (plastic or aluminum) on their lids and have no problems (myself included). i also use vertical sticks/branches as they lick to climb and perch from it (however it can lead to problems) and I keep it nearly straight up and down/vertical to prevent molting on it. If you get a more difficult species however a great material is the
shelf liner material that looks like little connected balls.
As for the process itself the mantid will split around the middle on the top of their thorax as they hang from a surface. From there they will slowly pull themselves from the old skin and will hang from that until they dry. They start by freeing their head and forearms first, then work their way back to their abdomen and walking legs. Typically the molt itself takes only 5 to 10 minutes, but they will usually hang from the old skin for an hour (or much longer) to dry before moving away.
They will refuse food 24 hours or so before the molt, and will not want to eat until about 24 hours after finishing too. Afterwards they are hungry from the experience and willy be ready to eat.
If the mantid does not have enough room during molting it will become trapped and will suffocate in the process (there is nothing you can do as their new bodies are so soft you will literately rip them apart if you try to help). Also if they fall before properly hardening their new skin, they will become deformed. The most common are problems with bent walking legs or nonfunctional forearms (unable to eat normally).
Depending on the severity of the deformity, they can be nursed until they molt again (as they molt they can regrow body parts and fix problems in a molt or two). I do however have a Ghost mantis with only one raptor forearm. It was that way since I got it at L2 instar (perhaps born that way) and never did regrow another arm of any kind, not even a nub where it would be. It has learned to live that way and can eat smaller prey feeders fine, and lately can eat bluebottle flies and waxworm moths without issue.
Here is a site that the author put together
the various stages of the mantis molting to show it from hatching to adult. I find it really interesting and it should help clear up any questions of the process itself.
