One of two ways, really, either use a liquid cleaner and a velvet pad cleaner or buy a mechanical device for cleaning vinyl. The vinyl cleaning machines cost between 30 and 300 pounds on average and will obviously vary in effectiveness. I have no experience of any of those machines so can't comment.
I use
This stuff with
One of these for cleaning, they do a good job.
The fluid is basically about 60% isopropyl alcohol and 40% demineralised water and I sometimes use that mix which seems to work ok. I'm told there is also a small amount of some kind of detergent in the commercially available cleaner but I haven't been able to verify this or find out what it is, if indeed there is any detergent included.
Recording from vinyl to WAV, FLAC or mp3 file is a very time consuming process as it's preferable to record each track individually rather than one whole LP side at a time. And in my personal opinion it's a waste of time recording to mp3, the quality loss kinda negates the whole process.
There is a free version of software named dbPower amp with an Auxillary module available for recording that does a good job, I think there's a link to it in V_R's software links thread but if you can't find it PM me and I'll host it for you for download. It's quite legal, it's a freebie.
The freebie dbPoweramp, however, won't record to FLAC, only WAV, but that's quite ok. I hope you have lots of spare disk space for this endeavour btw. A good time saver - and I've offered this before - is send me a list of what you want to convert and I'll send them to you in FLAC form.
Lots of the music I have I have purchased in more than one format in the past, the most common being vinyl and CD, so morally at least it's sortta legal
( << that statement may be the subject of an edit, I'll have to think about it).
Anyhow, you've bought them, so if you can shorten the process - why not?
Audacity, another freebie software program, will also suit your needs for recording but it's not as good as dbPoweramp. I bought the full version of dbPoweramp, btw, which converts music files and CD's to FLAC but which, oddly, doesn't have a record facility.
And unless your turntable has a built in RIAA preamp stage you will need an external device for signal matching, a cheapie on Ebay or Amazon will set you back £20 / 25.
Good luck and if you need any help just ask here
EDIT: Dishwasher's a definite no-no!
Have you seen what dishwashers do to glassware after a while?