i'm gonna tell you a strategy that will save you a lot of time.
first download the majestic tool bar.
search any keyword that is a buyer intent keyword. or any keyword in general you find.
then what you want to do is see the first page or second page ( or ANY page ) that have weak sites. how do you find out if a site is weak?, use your majestic bar and see the ROOT domain stats. see the reffering domains and external backlinks. then see TF. if these 3 are low, that means you have a weak site.
this means that this site will be ranking for LOW competition keywords right?
go to semrush.com
type in the domain of the weak site you found
and you'll see the keywords it's ranking for. those will be low competition keywords.
then type that keyword again in google, see the SERPS for that keywords, take out more weak sites and put them in semrush and you'll slowly start to find a lot of low comp high volume kw's that weak sites are targetting.
this is a strategy i have been using and it's quite effective. you will have an endless supply of low competition keywords and you will be opened to multiple niches.
i use long tail pro to see the competition level ( you can download cracked version of it as well ) with this and manual research. you want the long tial pro KD to be less than 30. if it's less than 25 then that's a truly low competiiton keyword. i usually see what kind of links the top 10 are building and how old are the sites.
remember to do manual research. fuck what the tool says, the metrics of anything, especially PA/DA and all that shit , all can be manipulated. these metrics just give you a little insight on how difficult the keyword is.
please read this so that you understand how tools are in accurate
https://www.blackhatworld.com/seo/w...ake-your-own-calculations-2-087-words.935960/
@SpoonFeeder has also given a very helpful tool you can use to aid in your research.
further more, read the ' keyword reserach section ' of this thread :
https://www.blackhatworld.com/seo/the-ultimate-blackhatworld-thread-repository.915304/
use wikipedia and type your niche in and you will find many sub categories. those are keyword remember that, read quickly the article and find keywords and keep entering them in Long tail pro or whatever your tool is.
soon you will begin to get alot of keywords you can target without a hassle.
keyword reserach is an art. learning it takes time.