Liksom means 'like', but it can't be used in all the same contexts as the English word.
There are two main situations in which you can use liksom. The first is if you're making a comparison, in which case liksom means 'in the same way as', 'just as', 'similar to'.
The other time you'll hear liksom is when it's being used as a so-called filler word or discourse marker; those small words that plug gaps in sentences when you're not sure what to say next. There are plenty of these in Swedish, with other examples being typ and alltså, and they correspond to English filler words such as 'like' and 'um'.
You'll often use it when searching for the correct phrase to follow it, for example 'hon var liksom… trevlig' (she was, like… nice). In this sense, you could translate liksom as 'sort of' or 'kind of'.
As a filler word, liksom's position in a sentence is fairly flexible; you can use it in the middle of a sentence or at the start or end: hon var trevlig, liksom (she was nice, basically) or liksom, hon var trevlig (like, she was nice).
As is the case with filler words in most languages, you'll occasionally hear some people grumble about the overuse of liksom, but these particles serve a purpose by showing that the speaker hasn't finished talking yet.
They can also be used to soften a sentence, but just be aware that if you use them a lot, you might end up sounding unsure of what you're saying. And while it's a very common word in spoken, colloquial Swedish, especially among younger Swedes, you should err on the side of avoiding it in written language.
För mig är det svårt att förstå, liksom för många andra utlänningar
It's hard for me to understand, just as it is for many other foreigners
Det där var inte kul liksom
That wasn't, like, cool