Sequencer: Record tracks

Go to menu Window => Sequencer => Main/Recorder.
If you have a MIDI keyboard controller connected, then change the recording channel from Unchanged to channel 10 (it is placed on the screen before the record option). If you want to use the onscreen keyboard at the bottom of the window, then change the melody channel to 10.
Click to place a checkmark at the options Record and Ticks.

Now when you play on your keyboard, you will hear percussion instruments.
Choose one of them and play a rythm pattern that is 2 bars long (1-2-3-4-1-2-3-4).
Now click on play.
The metronome will start to Play.
When the first 2 bars have past, play your rythm pattern 5 times.
Then click on Stop. Go to menu Edit => Quantize events and click on OK.

No click on play and listen if any of the played patterns sound as intended.
Select those 2 bars by deleting the other bars with menu Edit=> Delete Bars.
Don't delete the empty bars 1 and 2.
If none of the patterns sounds right then undo both the Quantize and Record action in the Edit menu and try again.

If you find it dificult to play the notes in the correct timing, then you can quantize with resolution 1/8 instead of 1/16. But if your intended pattern needs to play 1/16 notes, then record in a lower tempo. If you are playing a tempo in triplets then choose a resolution in triplets.

Find a few other drumsounds and record and quantize one or more notes with each. When you drumpattern is finished copy it to 6 bars.
Edit => Copy events: bars 3 thru 4.
Edit => Paste events: Insert at bar 1.
Edit => Paste events: Insert at bar 5.
Now switch Ticks off, we don't need the metronome ticks anymore.

Click on the Instruments column in row 11 and select 35-Fretless Bass.
Change the recording channel to 11 and click on Play.
Play one note at the start of each bar beginning at bar 3: C, F, C, G.
Quantize and play to hear if it sounds right.

Click on the Instruments column in row 12 and select 48-String Ensemble 1.
Change the recording channel to 12 and click on Play.
Play a chord at the start of each bar beginning at bar 3: C, F, C, G. Quantize and play to hear if it sounds right.

Now copy the recorded tracks 3 times.
Edit => Copy events: bars 3 thru 6.
Edit => Paste events: Insert at bar 7.
Edit => Paste events: Insert at bar 11.
Edit => Paste events: Insert at bar 15.

Click on the Instruments column in row 1 and select 73-Flute.
Click to place a checkmark before Loop, change the recording channel to 1 and click on Play.
Start improvising a melody and continue to play many repeats.
When you think the last repeat was a decent melody, then click on Stop.
Only the recording of the last repeat is kept.
Do not quantize the melody.
You have now finished your musical masterpiece.