Usually the word "No" is very small but It is difficult to say "No" to Someone who you loved. What's the reason behind this why we can't say No easily?
The answer is there is 3 reason behind this. First sensitive nature we think that is he/she hurt from my "No" . Second one you are afraid to say No to power personality for example your boss. Third one that your are over adjusting to see people happy every time. If you say yes all time this will give chance to people to miss use you every time.
Here are the some tips on How to Say "No" .
You can't say "No" suddenly because when any drastic change is found on you or you become rude that can be negative for you. We can start with indirect No. You can say him/her please give me some time or say that I'll answer you after checking down. That means you are not negative from front and indirectly you said "No".
When you are talking with powerful authority you can add respect to say No for example "Thank you you for considering me I genuinely want to do your work but unfortunately I have to do this work extremely urgent. You can give excuses but with respect.
One more tip is that you can use emotional weapons Like you can say that I promised my family you Know my friends now a days I'm in struggle in etc case. Use any of emotionally crunch.
4.You can Say No indirectly with the help of other Bait that your opponent don't want it. You can say that "I'm Sorry I can't do that But I could do this for you". This will helps you to maintain your respect to others.