As for deep cleaning:

You'll probably want to do a thermal paste replacement, if you haven't done that yet during the time you've owned it.

While the laptop is open, you can use some kind of air blower to blow the dust out.

While you have the keyboard out, you can use a cue tip or damp cleaning rag to clean the area and edges where the keyboard went.

Avoid rubbing alcohol on anything except the top exterior of the laptop, as the alcohol can melt some plastics, especially the keyboard springs.

#ThinkPad