Edited 5/30/19 to remove corrupted video.
Okay, so I've noticed the LASO checkpoint sharing threads are still getting a lot of attention, and while the Halo 1-4 LASO playlists are near-impossible for most of us without the checkpoint share, the ODST playlist is significantly easier (though still a definite challenge). Note from the start that this is not a checkpoint sharing method guide!
First things first -- There are two ODST LASO playlists, but you are going to want to choose LASO NON STOP ACTION, as it is the shortest and easiest of the two. Next, decide whether you want to do this solo or with a team. There are pros and cons to both choices. Some are claiming that playing with a group does not guarantee all members the achievement. While I can't confirm this from personal experience, you can read about others' experiences here: ODST LASO checkpoint
If you choose to play solo, you will be sacrificing additional firepower and experience. However, you will only have to worry about your own deaths, not your teammates'. Playing solo also gives you the ability to speed through a lot of the game. IF YOU CHOOSE TO PLAY SOLO, it is important to note the IRON SKULL WORKAROUND.
If you die for any reason, press Start --> Save and Quit --> Resume. This will allow you to restart at your last checkpoint instead of starting back at the beginning of the mission. Sure, there will be load times, but they will give your nerves a much-needed break. As many know, you could just hook up a second controller to revert back to previous checkpoints, but then you risk loading your guest account into dangerous areas.
Whether you've decided to play solo or in a group, it's time to prepare. Here are some tips that will make things significantly easier for you and your friends. Keep these tips in mind throughout your run.
1. Load up the mission NMPD HQ (not LASO) and place a piece of scotch tape or a sticky note over the sniper rifle's reticle. Now, GENTLY trace the circle onto the piece of scotch tape, etc. Now, you will have a make-shift reticle to help increase firing accuracy. If you get into a vehicle, your reticle will be about an inch above your gun reticle. I suggest you do the same for your vehicles, if necessary.
2. Always keep an eye out for plasma pistols and beam rifles. These are must-haves for this playlist. Make good use of your ammo, because the Famine Skull will be active, giving you and your teammates less ammo than before. Plasma charges will strip brutes of their shields immediately, and beam rifles will take their shields down in two to three shots, depending on placement (aim for the head, obviously
3. Use your best judgment as far as which sections should be run through and which should be taken slowly. Likewise, some sections of the game require you to kill every enemy before advancing, while some are timer-based. For instance, toward the beginning of ONI Alpha Site, you can wait at the bottom of the stairs after killing a minimal amount of enemies, walk toward the door that needs to open, and bypass a large remainder of enemies. Toward the end of ONI Alpha Site, however, you must kill all the enemies before getting on the elevator. Choose your firefights carefully, and explore your options.
4. If you find yourself in a pickle, remember that some of your AI teammates are invincible, and they fire an infinite amount of bullets, no matter what gun they're using! Hand the invincible guys the Spartan Laser or Rocket Launcher, and sit back and watch the show!
5. Follow a guide. I found a fantastic video guide created by Halo Completionist that highlights several helpful hints and routes for completing missions. Note that he is running the playlist SOLO. He repeats some of the tips I have already mentioned, but will provide more specific help along the way. Shoot him a "like" if the videos help!
6. Lastly, don't be intimidated, and take your run one mission at a time. If you are running solo, remember the Iron Skull workaround I mentioned. This LASO playlist isn't near as bad as the others, so don't feel like you can't do it! If you are getting frustrated, take a short break and come back to it. Good luck!
Here is Halo Completionist's LASO guide:
M1: Prepare To Drop (opening cinematic)
M2: Tayari Plaza
M3: Uplift Reserve
M4: Kizingo Boulevard
M5: ONI Alpha Site
M6: NMPD HQ
M7: Kikowani Station
M8: Data Hive
M9: Coastal Highway
M10: Epilogue (closing cinematic)
I hope this guide helps someone out there. Let me know if there is anything I missed or could add to help. Good luck!