Go get a 2-octave USB keyboard. I love
my AKAI LPK25 and it was only 60 bucks. You can get
a Korg Nanokey for $40 but they are far inferior in my opinion. I'm a very poor keyboard player but it's far, far better than manually inserting notes as far as stimulating new ideas.
Now, ready for the secret to writing a hook? There is no secret. One thing you can do is just steal something you like and change a few notes. You might feel dirty at first, but it's a good way to focus on the things you really, really like about your favorite artists and making it your own.
Once you've got your keyboard, loop your chorus, bridge, whatever you want to be "hooky" (as has been said, the word hook is overused, thoroughly misunderstood, and doesn't apply to a lot of musicians.) Your goal is to just freely experiment with note selection and phrasing (the intensity, frequency, and timing of your attack). It's okay to reject idea after idea, this should be a learning process for you at this point.
For me this has always been very easy and natural, but some people never, ever get it. You can get blood from a stone by just hacking away, but I recommend a different approach:
You need to familiarize yourself with at least enough music understanding to know what chords/notes go well together.
Almost all hooks are melodic, so if you don't understand how musical notes work together, you're reduced to being a monkey trying to write Shakespeare. You should learn at least the major and minor scales. If you're new to keys, start in the key of C major (all the white keys). Any note you hit that's white will sound somewhat good with a C major chord.
Sometimes a simple key change can result in a "hook" sound (God I hate that word). I would start there, just change your key from G to C, D to A, C to D, etc. You may hate this band but the end of Bon Jovi's "Livin on a Prayer" is a great example of how compelling this type of change can be.
Keep in mind your goal is about as easy as drinking coffee while standing on your head if you don't have any musical knowledge. Your question was basically "how can I be a more compelling/entertaining songwriter" and there is no easy answer.
Nibb High fooball rules!