Recording over Side A With Side B?? help??

I have Beta 1.3 and am confused about how to pause or stop the recording and resume without recording over my first section.My playback sounds like two simultaneous tracks over each other.I exported as a AIFF file and that was ok until I heard the playback.
Can’t I export the whole cassette recording as one single audio file? If so, what do I have to do to avoid my tapping over my first section or Side A with Side B on my cassette?

Mr Confused

based on what I think you said and asked:
do NOT STOP after side 1!

here is how i do it (after a test run to set the levels)

push start on cassette (avoids noise spike in recording this way) then
push pink/red round button to start recording
tape ends playing - push the blue captains bars to PAUSE recording
let tape run out to get to start of next side then
flip tape and start cassette machine again then
push blue bars to restart and continue recording
tape ends playing
then push yellow/orange square to stop audacity
now you have one track with both sides of your tape

diddle as needed (i would amplify or normalise to get max sound)
then export as wav and burn a cd or whatever

if you stop and then start you will get two recordings
and unless you time shift one (or cut and paste or whatever)
they will play together and sound like they are on top of each other

Method 1
To resume recording on the same track after pressing “Stop”, use the keys “SHIFT+R”
“Shift+R” is the shortcut for “Append Record”. http://manual.audacityteam.org/index.php?title=Playing_and_Recording

Method 2
Use the Pause button (shortcut is “P”) to pause the recording, then use the Pause button again (or “P”) to resume.