There are lots of useful websites out there which will help you to work out which of the main political parties has policies which you are likely to find agreeable. This is one of the best. If you've not decided how to vote you will probably find it helpful.
The only thing I have against this particular website is the strapline: vote for policies, not personalities. It seems to me that if I am voting for someone to represent me (and bear in mind that is what you are voting for; we don't elect a government, we elect an MP to represent us) I would rather have someone with integrity than not, even if I largely disagreed with them. "We have serious problems to solve, and we need serious people to solve them", as President Andrew Shepherd would put it.
Just something to bear in mind,