According to JMDict, かける is a word with around 37 definitions. The idea of memorizing all of these definitions is enough to make anyone think twice about learning Japanese at all, but even taking them one by one can be daunting if it’s not clear which one applies to the given moment.
It’s my belief that all of these “definitions” share a common abstract idea, in the same way that the English words “run” or “get” can be used in a multitude of ways that all make intuitive sense to a native speaker, even when encountering a new collocation for the first time.
Personally I find it especially helpful to split this overarching abstract into three more specific (though still widely applicable) glosses.
かける meaning 1: “set upon“
・メガネを掛ける set some glasses upon your face
・腰をかける set your body down on a chair
・負担をかける put a burden on somebody
・心配を掛ける lay your worries on someone
・金を賭ける set money upon the gambler’s table ★
・水をかける to sprinkle water onto something ★
・10かける10 ten times ten; ten set upon itself ten times
かける meaning 2: “expend into“
・スパイスをかける to add spices into a dish
・金を賭ける to bet money ★
・腕によりをかける to put effort into work
・水をかける to sprinkle water onto something ★
・時間を掛ける to spend time doing something
かける meaning 3: “engage or activate“
・かける (standalone): the standard “use” action in video games (“open” the door, “pull” the lever)
・アイロンを掛ける to iron clothes
・電話をかける to make a phone call; to use the phone
・鍵をかける to engage a lock
Each of these three broad meanings fall under one single overarching meaning, which I think of as “raise up“, because to me it evokes the idea of a movement upwards, whether abstract or concrete, towards some end. In the first case, you must “raise up” that which you wish to “set upon” something else. In the second, you figuratively “raise up” that which you wish to spend (a parallel may exist with あげる, where you “raise up” what you wish to give). In the third case, the thing that is being “raised up” is your own hand, to manipulate objects.
(Examples marked with a star are those which I feel work nearly as well in either of the first two groups)