The strain suggestion depends on what you are looking for as each strain has different attributes. I would determine what you are looking for in your strain. Do you want it to give you an energy boost? Do you want to relax? Do you want a psychoactive effect?
Once you have this determined, you can drill down a bit more and decide what additional effects you want in which case you can pair terpenes. For example, a strain with the terpene linalool will be more relaxing and calming than one with limonene that will be energizing.
If all else fails, smell it! If your body is drawn to it, buy it!
Different strains provide different effects, so step one is to figure out why you want the cannabis in the first place. Do you want it for daytime or nighttime use? Energizing or relaxing? Is it for pain, mood lift, appetite stimulation, etc? Do you want a lighter psychoactive experience or a more dominant one? Andrea gives a great answer to your question in the video on this page – check it out. There are so many strains to choose from these days to tailor your experience.