Try to Beatmatch them by pitching (speed up/slow down) one of the songs.
NOTE! It's handy to SET a CUE point for a song at the first beat, so you can jump back if you mess up or can't figure out the pattern anymore.
By pitching you can set the speed of the song, but the beats are still playing after eachother.
Try to use the Pitch Bend buttons [+]/[-] to speed up/slow down for a few seconds so that both beats play in sync.
(On vinyl you use your hand to do the trick).
HINT: If the beats are almost in sync and they have only a small difference (or they just start to drift apart), you can try to correct this with the Pitch Bend function. This slows down or speeds up one song temporarily, until the beats are matched exactly. Use this function only if the difference is really small, otherwise it is probably easier to hit Cue and Play and try again.