I'm using serum ketone levels - it's about the only genuine measure I've been able to find that is independent of water weight and bloating. I'm tracking weight as well to see what correlations there are between ketone levels and scale. Also, so far ketosis has meant more energy, better sleep and fewer IBS symptoms. I'm tracking those as well. So far I'm not tracking macros, just limiting my carbs to veges and choosing more fat when it's practical and palatable. There's loads of room for tweaking! It could take 2 weeks to get fully into ketosis, though.
Weight = 88.4kg
Ketones = 0.4mmol/L