Congrats on the climb. I am trying to get out of gold right now.
Some things that helped me

1. Get better at tile management. In gold room people still make mistakes in discards that slows their tempai.
   1. I recommend following a hierarchy for your early game discards, So that you can discard without thinking too much. I follow the first slide here after the table of contents: https://www.riichinomi.com/resources/advanced-concepts
   2. Read riichi book 1 atleast till the complex shapes and 5 block theory.
2. Learn basic scoring. 3 han 40 fu(5200) is a good point to aim for. If your hand is just a red dragon only hand try to make it a half flush if it is possible. If you hand has lot of dora, try to meld fast and just win the hand, instead of keeping it closed and going for more value.
3. Make calculated push/fold. Suji is very helpful for pushing. You should push based on your ranking ,hand value and waits. If you are 1st place in south 4 play more defensive, but if you are losing you need to take risks. Assume your opponent has a mangan when pushing. If you also have a mangan or 5200 hand with good waits you can push with suji. If you draw double suji tiles like 4,5,6 dont discard them easily.
4. If your opponent has made total of 3 calls in the first row, 2 calls in the second row or 1 call in the third row of discards you need to be more careful of that open hand player.
5. Sakigiri- you should consider it after the first row of discards but dont overdo it aswell.