I came across this idea in psychology about practising self love, appreciating your worth by telling yourself that you love yourself. I'm interested in the Islamic perspective of how we should view ourselves to increase self esteem- it feels a bit dangerous to say I love myself as I don't want to feel prideful or hubristic.

Could you point me to any ideas in Islam which discuss this concept? How should we feel about ourselves?

We have in Islam what’s called self inspiration ( talqeen Nafsee). This is looking at what Allah has blessed you with. The purpose of which is to appreciate and be grateful to Allah.

The Quran encourage us to reflect on ourselves ( self reflection) in order to be grateful to Allah.
51:21

It also encourages us to speak of Allah’s blessings in our lives. 93:11