I struggle too.
It's not easy to stop judging others. I was devistated to learn that I was prejudiced! It's something I struggle with daily now. Here's what I know. If it's an assumption based on general knowledge, then it's a judgement. It's like the assumption that all Mexican immigrants are on welfare. That a judgement! The truth is that some are on welfare, other's are migrant workers, other's are blue collar workers, other's own businesses, other's have well paying jobs!
Anything based on a stereotype is a judgement also. A stereotype is that all black teen boys are in gangs. The judgement would be that any black teen boy is a gang member, again not true. (I have a very judgemental friend by the way)
BUt what's helped most is understanding what was meant when Jesus said as you judge so will you be judged. First, we are all at different spiritual "maturity levels". So, we judge a person for having an abortion as an awful sinner. That person's spritual maturity is such that they do not know Jesus and His teachings (or Allah if that person's Islamic etc). Your (whomever's reading) level is such that you know Jesus and some of His teachings. If God were to judge you right now you would be expected to have lived by all the commandments without fault. So if you refused to help mom go shopping, you're an awful sinner in the same line as the one who had an abortion. If you knew Jesus and most of His teachings, then that judging would be even worse. And upwords.
The best way to stop being judgemental is to educate yourself. It's like the saying of walking a mile in another man's shoes, without the knowledge of their position you don't have that ability to judge at all. Going back to the abortion example, it'd help to learn the reasons why abortions happen in the first place. Things like age and lifestyle and possible histories of abuse. Nothing said or done will change that abortion that happened, but understanding the background will help you understand the action. It can also be used as a way to help instead of judge. Somewhere in the Old Testament it says to study to show thyself approved, it's rather good advice!
GOd bless!