DYI or kite shop???
Do U have repair kit?
First up find leak then make decision....
1) bowl/bucket water with shampoo or washing up liquid in - makes bubbles to spot leaks.
2) pump up - isolate all struts - clamp off -
3) which every goes soft - re-pump and paint (or use a cloth) water over tube - if U have a swimming pool available - much quicker - hold each section under water to look 4 leak(s).
Do a search for bladder repair or valve repair - lots of videos - Search on "Tear Aid"
Same approach for valves search on "Kitefix"
Good skill to learn - but equally shops are set up for this...
Cheers
AP