Needing help on getting ROMs working on regular DSi

I finally decided to try it, and there's problems already.

I downloaded Moonshell to "convert" the ROMs to work on the DSi, but the files of it (Moonshell) I get don't work.

Also on my list of problems is that I'm trying to open the Homebrew channel via DSi Sound (like videos say), but it "couldn't find compatible files".

And, I'm trying to do this without buying a R4 card, because I'm seeing numerous videos around the internet saying you can. >.<

So..I know this is a lot but if you guys can give me some tips on getting this to work, that'd be great.