I am always making a point of doing things constructively.　私がいつも心掛けていること。(Contructively means, the things you do have a purpose. )

I am always making a point of saving energy.
私は節電を心掛けています。

But my husband can't do it.
でも、旦那はそれをできません。

He returned home very late last night.
Then he took a bath and ate a dinner while watching tv. (ate and returned are conjuagated in the past. The word takes is conjugated in the habitual tense. You should use the past conjugation of that verb, took instead) 
昨夜、遅くに帰宅した旦那はお風呂に入って、テレビを見ながらご飯を食べました。

It looks like he fell asleep while eating dinner was sleeping just like that.
彼はそのまま、寝てしまったようです。

Because When I woke up this morning, I found that he had left the was leaving TV,light and air conditioning on.
だって、私が今朝起きたら、テレビ、明かり、エアコンがつけっぱなしだったんですもの。

I hope that he keeps his eyes open for potential saving energy savings too.
彼にも節電を心掛けて欲しいものです。

For your information, I usually get in a become bad mood in this case.
ちなみに、大抵、そういう時は私は機嫌が悪くなります。

ぷんぷん

(Pretty good entry. Have fun learning English)