This applies to nanos only (since I haven’t kept a significantly larger tank), but my main tips are patience, keeping it simple and learning your tank. Included a pic of one of my old tanks as well that’s now shut down. I’m sure plenty of ppl may not agree with my approach, but it’s what’s worked for me for years.
As for patience, these started as quarter sized frags and this growth took about 2-3 years, so nothing happens fast.
Keep it simple, good lights, a powerhead, heater, ATO, good filtration, water changes, good cleanup crew, and (if needed) a simple dosing regimen. Ive never tested any parameter on my tank other than ammonia and nitrates when I’m cycling and salinity when I’m doing a water change. Dial in your lights. Start off with 20-25% water changes weekly. Once you approach the 9-12 ish month mark, move to bi-weekly. I currently am doing water changes maybe once every couple months. As for dosing, until you slow down on water changes it’s likely not needed, but dose something like AFR, ATI essentials or Red Sea alk/ca/trace. Pick one you like. Pick a nominal dose based on your tank size and dose consistently, e.g. every other day or for example, water change Saturday, dose Tuesday and Thursday and repeat. No need for goofy equipment like an apex, trident, algae scrubber, skimmer, etc. on a nano, but if you have cash to burn, why not.
Learn your tank and livestock. My tank is in my main living area. I walk by it 100 times a day. I stop and take a quick glance at it maybe 1/4 of those times. Watch your fish, watch your corals, see how they look when they’re happy so you can quickly spot if something looks off and adjust, e.g. a coral that consistently has thick flesh like my chalices has been showing thinner flesh for a day or two (a lot of issues are usually resolved with a quick water change on a nano). Address issues quickly, see a dead snail, pull it out, see aiptasia or vermatids, deal with them. Dont let stuff linger.