The same way as it is possible to have sex with a chicken, but you shouldn't- it is also possible to mine with a laptop but you shouldn't.
The reasons are:
You will not make any significant money, maybe $5-10 a month , MAYBE!!!
You WILL destroy your laptop. The most important thing for a miner is cooling. A laptop crams as much as possible in a tiny space. Cooling is very hard to do.
Not to mention putting that much load on your laptop for extended periods of time will absolutely wreck the battery. If the laptop has a replaceable battery and/or is an old junker, I'd say go for it.
That said, if you use your laptop for any purpose (work, school) I would advise against it.
That being said, I first got into mining myself by mining off my laptop which led me down the path of setting up my first mining rig, the rest is history