The screen (or the window if doing TWR) is more important than the strip bay!
IMHO complete and utter rubbish as far as radar is concerned, especially as the original poster says they are a trainee!!
The more green you are, the more important the strip bay is.
As you get experience, you can rely less on the strips and do more off radar.
At the beginning of your career getting the strip scan sorted is very important. Knowing the information it can give you and the triggers that information provides is important.
As you look at a strip, ask yourself of every aircraft:
"Where is he, (makes you look at radar, find the aircraft and start planning, even if not in your sector yet)
where does he want to go, (extends the planning process)
what level does he need to be, (as above)
what is in his way
Wha can I do for him right now**"
The more you get used to the sector, the quicker this process will become. Don't be too rigid with your scan - a lot of time conflicting aircraft are in different bays to each other - if you can give a climb or descent to an aircraft in one bay it often means you can do something with another in a different bay (which develops expedition).
Remember once you have done this though, to return to where you interrupted your strip scan.
Don't forget if using shared airspace there may be standing agreements that you do not work that are not highlighted in one particular bay i.e. don't forget adjacent traffic!!
Even as a very experienced controller, having a good strip scan process can get you out of the poo, or help in unusual situations. As you progress, your strip scan will become extremely quick and you won't have to think about it.
A regulated strip scan will help you build up and maintain a situational awareness - if quizzed, you would actually be able to pinpoint the position of aircraft on radar with a fair degree of accuracy without looking at radar - if you have kept a good scan cycle.
I think a lot of HF is bunkum and job creation, but the do say that it takes 10 minutes to fully get a situational awareness and build your mental picture after sitting down - any breakdown in scan, particularly when fairly inexperienced, will mean that it will take a finite time to rebuild that picture.
Your scan will adapt and evolve as you get more exprienced - it will feel unnatural to start with because it is only natural to expect that looking at a radar will give you all the answers (it will, but you need to know where to look and it depends on how much info (how busy) it is giving you).