なりに

When used as a noun, なり often presents an example group from which something exhibits traits of, regardless of whether that group is actually a good example of the trait being described. This use can be translated as 'for (A) do to (C) in the way of (B)'. Or more simply, 'to do its best in its own way', or 'to do as much as one can'. This use stems from 形(なり), meaning 'shape' or 'pattern', and can be thought of as meaning 'in the pattern of'.
In these sentences, (A) will be a specific example from within a group, (B) will be representative of the whole group, and (C), will be the trait or behavior in question related to (B).
Either of the case marking particles に or の will come after なり, depending on whether なり is linked directly to a noun, or is being used adverbially. なりに and なりの may follow almost any word in its plain form, with the word it follows being the group or quality that is being represented.

• 自由(じゆう)時間(じかん)が増(ふ)えたら、増(ふ)えたなりに有効(ゆうこう)に使(つか)いたい。
  If I get more free time, I would like to use all that freetime as much as I could.
• 広(ひろ)い部屋(へや)は広(ひろ)いなりのデメリットがあります。
  Large rooms have their own disadvantages.
• 彼(かれ)は仕事(しごと)が下手(へた)なりに、他(ほか)の社員(しゃいん)のモチベーションをあげてくれたりしている。
  For all of his lack of skill, he does his best to motivate other workers.
• 自分(じぶん)なりに頑張(がんば)ってみたが、やっぱりダメだった。
  I tried my best in my own way, but it was still not enough.

This use of なり is considered a neologism, which is a pre-existing word that has been adapted to have a new meaning or nuance. When used this way, なり will almost always express that (A) is not doing something adequately or as desired, but is doing the best it can based on the 'pattern' or 'mold' that it comes from.