My Commander Ironman Guide
First part:
Put base around Egypt so it covers Africa, Europe, Soviet Union and Western China
Build generators, hospital, living quarters
Base Assault: Do it as normal, be sure to capture the general and a cleaner for OP
OP: buy a security supporter that gives -1 doomsday per day to save you a headache, after that then focus on removing infiltrators
Initially all the aliens will fly are probes which are defeated easily by a lone interceptor, so you can focus on getting MARS and warden armor which will make the first part much easier as cleaner guns do next to nothing against them and a MARS will crush Symbiotes without too much TU usage.
Alien abductions: Don't go crazy with saving lives. Keep your guys together to support each other. Saving 5 should be enough. Otherwise play it normally with liberal use of smoke, c4 and stun grenades.
Cleaner convoy ambush: Don't bother with prisoners, the MARS can take a lot of punishment while you pick the rest off. Don't damage the trucks for greater rewards.
Cleaner Data Centre: Use lots of C4 and run through the place fast. Hopefully you have warden armor and a MARS to soak up the damage.
Cleaner leader: Split 2-3 guys to attack the smaller buildings on the right to hack computers while the rest go for the leader. You can capture the leader by hitting him with C4 once and then smoke/stunguns/stun batons
VIP: Fairly simple. Keep your guys together.
While it's all going on get aerial weapons unlocked, another hanger and interceptor, radar arrays and alenium generators ASAP. Money is a big bottleneck and don't be afraid to sell spare alloys, alenium if you can afford to.
Skip accelerated weapons for lasers.
Mid to end game:
Don't go crazy with the second base until you are ready. Security supporters can reduce panic until you are ready for another one.
Build 3 missile defenses, 3 planes, 3 radar arrays, the training room, second workshop.
I built 5 hangars so that I'd always have 3 planes ready at the main base while building another for the new base.
Focus on the air war. You can rebound from losing all your soldiers but losing all your interceptors at once may be a deathblow.
If a mission is going badly just retreat. You can always shoot down a different UFO. It's worth waiting for the next tech upgrade, engineering project to finish. Time is on your side. Never fight at a disadvantage.
Cleaner base: If you have lasers and warden armor this should be easy.
Alien UFOs: For small UFOs, arrange a firing squad outside the door. Open and chuck a smoke grenade, maybe a stun grenade if you're cautious and break line of sight. Repeat until the aliens rush out and die to reaction fire or are unconscious. You can speed up the process with regular grenades.
For big UFOs, after you breach, don't be shy with the C4. Stun grenade anything that can be stunned. Machineguns and shotguns are king here.
For Alien bases: focus on finding the command center. Teleporting into a room with Sebillians it' going to be a bloodbath. If one unit has to be sacrificed while messing with teleporters, use the MARS as they won't be suppressed. Shoot, leave, and repeat with the whole squad.
Terror missions: If you have breathing room to take the panic penalty and not do them just do that. Otherwise its going to be ugly.