'To make a party' is perfectly acceptable but polite, old fashioned and it means something subtly different. It means coming together as a group to do something; as in 'I met some friends and we decided to make a party for an adventure' or 'The Jones family and the Smiths made a party for a picnic'. It isn't used to hold a party as an event. There you go; there's another one: 'To hold a party'. This infers you are the host. You can also 'host a party'.

Ok, now I am obsessing. ‘Since 3 years ago’ at the end of this sentence, jars. You can use this phrase, but it works best as a fronted adverbial; a phrase at the beginning of a sentence that describes the action that follows. However, more natural is to use ‘since’ to describe the point in time that the action started, defined from that point: i.e I haven’t been kissed since last summer or Since last summer, I haven’t been kissed. ‘Ago’ defines the point in time from now: i.e two years ago, I broke my leg or I broke my leg two years ago. So ‘Since 3 years ago’ jumps back and forth. However, this can be used in certain circumstances to describe the period from then until now, it’s best to get it over with at the beginning of a sentence. Of course, it can be replaces with ‘for 3 years’. Hey, that works better: I have been learning English for about 6 years but more seriously for 3 years. Or to clarify it was the last 3 years of serious study and it wasn’t the middle 3 (although that is inferred), how about I have been learning English for about 6 years but more seriously for the last 3 years.