Actually, you'd want to go with a decentralized, independent planning, and ideally independently supplied insurgency. Produce tons of RPG's, IED making material, et al, and put them in moderately sized depots everywhere in the country. Upon invasion, military is disbanded, pre-assigned teams grab stuff from their assigned depot and then bury it in the desert.
This is interesting, because it appears to be exactly what the Iranian trained Hizbullah organization did in the 2006 war. From the reports I read, they relied on buried stashes all over the place, operating independently in small teams.
The thing about war with Iran....I think anyone with eyes can see that the Iranian military is no match for the US. It will be destroyed in terms of its being a force capable of occupying territory or doing anything the US military could do. They can probably hide and launch rockets, but that's about it.
But what will the outcome be?
On the extreme nice-for-us end, bombing Iran produces no real effective response, some Iranians die, and maybe Iran's nuclear program is set back a while. Iran goes commando in Iraq and we deal with increased insurgency.
On the extreme bad end of the scale, WWIII breaks out after the region, including oil producers, from Pakistan to Israel bursts into flames of anger in the aftermath.
I haven't seen any convincing evidence to show that the most probable outcome of such a war would be good.
Why on earth would we get into a war when we have no real idea what the full consequences would entail?