What is the pattern for 'instead of x, y...' For example, how would I say, 'instead of x, we should do y'?
I find it hard to balance the sentence correctly in chinese.

Do I need to use, 反而 or 而且? Or is there some better method?
反而 is mostly used when something is contrary to expectations.
An example: Suppose it is predicted that there would be no wind, but there is a lot of wind, and after a while it starts to blow even harder you can say:

风不但没停，反而越刮越大了
    the wind not only hasn't stopped, but blowing harder and harder


而且 is used to give some extra information and is typically translated as "*and also; besides; and what's more; but also". 

You can use "而不是". For example:

我们需要的是能力强的职工，而不是吃干饭的
    What we need are people with great capabilities, instead of those who live off others. 


You can also use 与其..., 不如... which is translated as rather than ... , you'd better ....
An example:
    与其少买，不如不买
        I'd rather not buy anything at all than buy just a few.

Often Chinese wouldn't use a conjunction at all. For example (these 2 examples come from Nciku)

中国人不习惯用刀叉，更喜欢用筷子
    Chinese people prefer to use chopsticks instead of a knife and fork.    

我想上场，不想在余下的比赛中做替补。
    I want to play instead of spend the rest of the match on this bench.