• You can only safe by sleeping and by exiting the game. (The exit save can only be loaded once!)
  
• Fast travel is disabled.
  
• You take but also deal more damage.
  
• Threats are not visible on the compass.
  
• Locations show much later up on compass.
  
• You have to sleep, eat and drink.
  
• All foods lose their healing properties and do not regain them until enough is consumed to make you "well-fed."
  
• There are illnesses (Find a doctor or take antibiotics to cure them)
  
• Healing rates of RadAway, stimpaks, and other healing items are significantly reduced.
  
• RadAway and chems can negatively affect the immune system.
  
• Sleeping in a bed for less than 7 hours does not heal Hit Points.
  
• Ammunition has weight and total carry weight is significantly reduced for both you and your companions.
  
• Companions will not get back up if downed in combat until healed. If left unattended, they will return home.

The here listed perks are very useful in survival mode. They mostly focussed on survivability.

You should focus on one of the damage increasing perks for your weapons like Rifleman or Big Leagues. I recommend to go with Rifleman because rifles and shotguns doesn't consume that much ammunition and rifles can be perfectly used on long range. It's always good to be undetected in survial mode.

Lead Belly - This let you take less radiation from eating or drinking and at rank 3 no radiation from eating or drinking. Some times you don't have any other choice and have to drink dirty water or eat pre-war food. This won't be a problem with this perk.







Aquaboy/Aquagirl - At rank 1 you no longer take radiation damage from swimming, and can breathe underwater. Rank 2 makes you become totally undetectable while submerged. This is pretty useful but not absolutely necessary.







Lone Wanderer - Rank 1: When adventuring without a companion, you take 15% less damage and carry weight increases by 50.
Rank 2: When adventuring without a companion, you take 30% less damage and carry weight increases by 100
Rank 3: When adventuring without a companion, you do 25% more damage.
Rank 4: When adventuring without a companion, you have 25 more action points. You can also take Dogmeat with you and the perk will still work. If you decide so, Attack Dog could be useful to you.

Local Leader - With this you are able to establish supply lines between your workshop settlements at rank 1. You can build stores and workstations at workshop settlements at rank 2. Later more to this perk and why it is so important in survival mode.









Scrapper - Works perfectly with Local Leader. You can salvage uncommon and rare components when scrapping weapons and armor. (Rank 1 and 2) At rank 3 you get more from salvaging. You always need these components to build in your settlement.







Chemist - You are able to craft your own chems at rank 1 but more important you can make antibiotics by yourself.







With high endurance you also have more HP. In survival mode you die fast any way, but it's an difference if you can endure 2 or 6 hits.
Depending on your playstyle you want some other skills too like Ninja, Sneak or Mister Sandman if you are into stealth.
Toughness or Life Giver if you are into open combat.

Settlements are the way to survive in survival mode. In settlements you can socialize, sleep, drink and eat safely. I recommend you to build in every settlement at least one water pump. What the most people don't know is you can actually refill beer bottles, Nuka-Cola bottles and pretty much every other bottle in the game with purified water on a water pump. You can also directly drink from the water pump without taking any radiation. You should also have at least one bed (I mean no sleeping bag and no dirty mattress.) in which you can sleep 24 hours at a time. You won't be tied anymore after sleeping 8 hours. Settlements are spread all over the Commonwealth, so you have basically every time you are in trouble an settlement close to your current location.

Lokal Leader really helps you out by building in your settlements. You can set up supply lines which basically connect your settlements with each other. If you have for example 200 wood in Sanctuary but no wood at Bunker Hill set up an supply line and you can use all the materials you have in Sanctuary.

*minor spioler in this section*

As you all should know, fast travel is turned off in survival mode. Some of you may not want to travel all the way by foot. Well there is an alternative for all of them.
If you become a member of the Brotherhood of Steel you will gain access to vertibird signal grenades, with these grenades you can call a vertibird from the brotherhood of steel which can fly to every location you have already discovered. (no you don't have to side with them at the end of the storyline)
How to use it: Equip the grenade like any other grenade in ur inventory. Then throw it on the ground. Wait for a few seconds and you will hear the noises of the veribird. After the vertibird has landed you can enter it. Open your pip boy and choose on the map the location you want to go to. The pilot will start the engine and you will actually fly to the location. It's far more faster than traveling by foot.
Where to purchase the grenades: You can buy the veribird signal grenades from Proctor Teagan on the Prydwen. (or from Tinker Tom at the Railroad HQ or from Ronnie Shaw at the Castle)

If you destroy the Brotherhood with for example the Minuteman, the vertibird fast travel service gets taken over by them. Same thing will happen if you destroy the Brotherhood with the Railroad. (Institute will not get the vertibird function)

You probably have to change the way you play the game. Hunt every animal down you find in order to get their meat. Stay hidden and have an eye on the environment. Keep your eyes open for mines and hidden enemies. Use V.A.T.S to easly spot enemies. Plan your travel routes to avoid enemies. Use every mattress you find to save the game (If your resources allow it). Focus on two or three weapons, for example I use an rifle, an shotgun and if I run out of bullets a machete. Take only with you what really need to survive. (You will not need 200 fusion cells if you don't use the weapon for it.) Don't fight a fight you can't win, run instead.
A few words about power armor:
Power armor is pretty useless if you want to sneak and some enemies can even hit you though it, but in the end it depends on your playstyle. (Power armor is still good and fun to play with) Be aware you can't swim in your power armor and some other things like sitting down on a chair aren't possible as well.

Leave a comment if you have any other useful tips.

If this guide helped you out please leave a thumbs up. =)