State of Survival has some mechanics that you may can leverage in your advantage with some of this quick tips.
UNLOCK HIGHER PLAGUE LEVEL
You can unlock a higher plague levels instantly by getting an personal invite, by using that method you can directly go to doing the highest plague level without having to do the ones bellow first.
The chiefs which take out the GigaCorp forces (zombies) get "First Occupant" crates. The important thing here is that you can rally the bunker/facility to share the rewards to all rally members. Meaning that you can get ~20/~40 crates from a bunker/facility for your alliance instead of 1/2 by taking it with a single person.
Note that you will need at least 1 minute till the rally launches, so make sure first that nobody else is going for your targeted bunker/facility.
To prepare for training events, you can only train a tier bellow your max available tier troop. Upgrading them when the event comes will net you more points.
For example if your highest tier troop is t8, consider training t7 to upgrade later.
WHEN TO USE X?
Generally you want to save anything you get from speedups to biocaps to save for a time where you can get multiple returns on it.
For example before using construction speedups you could wait for an sotf-stage or construction event which will give you some of them back.
BIOCAPS - try to combine with throwdown and/or special events to
ACTIVATE SECOND CONSTRUCTION SLOT
BUYING IN VIP SHOP
BUYING IN MARKETPLACE
CHIEF GEAR COMPONENTS - use for throwdown or sotf
MEDAL COMPONENTS - use for throwdown or sotf
LEGENDARY HERO FRAGMENTS - use for trowdown or sotf
LEGENDARY GENERAL FRAGMENTS - saving them till you get access to 3rd generation heroes should give you most of the value.
- Legendary Fragment
You can make the decision between throwdown and sotf, by gauging if your alliance is actively pushing for higher throwdown tier and has many members completing challenges. If its not a goal of your alliance it may be better to use them for sotf.
If a few of your alliance need to temporarily relocate and exact position is not so important consider having your leader port first so that all other can use "alliance relocators" instead of "advanced relocators".
Trading is not yet implemented in the game, so to exchange ressources you need need to use plundering as a workaround. To do that make sure that you have all your troops outside of your settlement (gathering, occupying, reinforced or in bunker), heroes you have in settlement do not matter. Then your trade partner can attack your settlement to get the desired ressources.
The attacking side should recon first and make sure that there are really no troops in the other settlement to avoid loses, this counts double if your trade partner is of a much higher level than you are.
READ INGAME GUIDES
Some infos in the ingame guide are quite good, consider reading it too.