Conflict and tension are unavoidable parts of any relationship. Whether it's a romantic, sexual, friend, colleague, or employer all relationships require communication and understanding. Many people are afraid of arguing and will avoid conflict at all costs, which in the long run can only make things harder.
Different people will always have different perspectives on things and the truth is that both persons view is the reality for them. The way in which we manage this conflict depends on our ability to say the things we mean (and feel), and to hear what the other person is saying (and feeling).
Expressing our needs and emotions is a necessary step to building stronger relationships. Instead of seeing argument and conflict as negative things, we can treat them as a way to see a new point of view and negotiate so that everyone's needs are being met.
Here are some tips to help you:
Listen without interrupting
Think about what you hear and how that is making you feel before responding
Put yourself in the other persons shoes, so instead of trying to justify behaviour or explain it away, simply acknowledge how it has made them feel eg. "That must be really frustrating for you"
Play the ball not the player, focus on the behaviour and how and why it bothers you rather than the other persons character or flaws
Start on the right foot. The below image is a list of things you could say, keeping in mind that the way the conversation starts is going to set the tone for the rest of the discussion (these are based on the work of Gottman). Use soft start-ups and communicate clearly. A great example of this is around phone use. You could say "I hate it when you are always on your phone" or you could say "I feel neglected and lonely when you are focussed on your phone". Which one might work better at opening up a dialogue and reaching a resolution?
If the other person is defensive or avoidant it might mean they are flooded (overwhelmed) so take a break rather than pushing the issue
If you are being defensive or avoidant take a break to think about what this argument is bringing up for you, is it your fear of rejection? does it remind you of a negative experience in the past? Being able to untangle the current issue from past issues is an important aspect of successfully resolving things
Approach your partner with unconditional positive regard, basically give them the benefit of the doubt. If we approach each other with kindness and compassion we can see that the behaviour and the person are not the same thing. They might be acting irrationally right now so ask what's going on for them rather than assuming they are just irrational or difficult
Lastly, be open to being in the wrong! Being prepared to accept that you might need to change your behaviour is an opportunity for growth. Conflict and disagreement are positive aspects of any relationship when handled well. Showing respect and empathy for each other and being willing to listen will ensure that the positive interactions in the relationship outweigh the negative ones.