Using my level 8, nearly maxed core level 2 account, I believe I have come across an effective strategy for beginner players pure derivatives of trial and error. And it is in this thread that I plan to share them in an effort to shorten the learning curve for beginner hackers:
The most important thing to do when preparing for a hack is scouting (You have a brief window to scout before you have to commit to a hack in which you can disconnect and then reconnect to renew the scout timer. You can do this as many times as is necessary to plan a hack, alternatively you could take screenshot and plan from the photo)
Here are some things to take into account when scouting a base to hack, bearing in mind that at this stage in the game you have 3 available viruses: The Beam Cannon(offence - 1 space), The Shuriken (offence - 1 space) and The Ice Wall (defence - 2 space). And 25 disk space (If you do not, it will take you a few days max to get them):
- Have they used all the connections on their sentry nodes or placed them next to one another? (If so, their antivirus will spread more slowly)
- Is their base a long snake design? (if so, Beam Cannons will be able to take their base as a level 1 beam cannon will take out an antivirus node before the hacked node gets destroyed by the antivirus, so you can just run up the snake)
- Do they have turrets? (If so, bringing an ice shield is imperative to your success, as a level 2 turret will destroy a node with 3 level 1 Beam Cannons installed)
- Does their base have LOTs of connections (if so, your best approach is the Shuriken/Ice Wall hack. Shurikens do little damage, but attack all the connected nodes at once. When protected by an Ice Wall, 2 Shurikens can happily destroy two turrets and an antivirus block in a matter of seconds)
- How far from their netConnections are their sentries? (If they are a beginner player, they will often have netConnections connected or a node away from their sentries, in which case a full frontal charge is best to destroy the sentries and prevent the antivirus from spreading)
- Where are there resource nodes and core? (This is important for the player wishing to advance his/her game, as resources and reputation - gained from a successful hack - should be your main incentives for hacking. If you are not sure if you can completely hack a base, ensure you install your viruses in a way that will either get you the core and protect it for long enough to download it, or get you resources.)
These in my opinion are the main things to look for if you have time and can be bothered doing a proper scout (feel free to add recommendation in the comments and I will update my list).
I often cannot be bothered to properly scout out a base, so I have also put together a 'Do it all' setup, for beginner players wishing to hack quickly and effectively without spending precious time scouting out a base.
The 'Do it all' virus composition goes as follows (as previously mentioned, I am assuming you have 25
disk space and the first three available programs. If not, you will get these within few days of playing):
- 2 Ice Walls (This is taking into account that your opponent may have one turret and one node that will be attacked by antivirus from 3 or more other nodes. Let the node you wish to protect get hit once or twice before you install the ice wall, as nodes will regenerate when protected) #note# It is tempting to bring more then 2 ice walls, as they are one of the most useful turrets in the early game, but they take up 2 disk space and you will often find yourself in full control of the base (no antivirus left) but without enough offensive viruses to finish the hack successfully. So unless you scout the base and decide you need more then 2 Ice Walls, it is best to stick with 2.
- 3 Shurikens (This is for those infected nodes, perhaps surrounded by a turret and 3 antivirus nodes if they have 4 connections , that you need to infect quickly. Using an Ice Wall to protect your node and then installing 2 or 3 Shurikens is extremely effective for these situations)
- 18 Beam Cannons (These make up the brunt of your 'army'. One of these will infect an antivirus node before your infected node gets retaken. Unless you are going for a full frontal assault on a sentry or turret - in which case you will need and Ice Wall -, use only 1 Beam cannon, as you will need as many as possible to clean up after you have taken control. If you have a few left over, then you will be able to attack again sooner too

And so concludes my rough guide for the beginner hacker!
Feel free to make suggestions and I will happily add them into the main article.
NOTE: I apologise in advance for mistakes I may have made in the text. I have not yet edited it due to lack of time, but I will in the near future. I also have several other things to add at a later date.