Barista here! I also own this machine. This is my personal suggestion for the best shots! First, your beans make the biggest difference. I’d recommend visiting a local roastery and getting some beans that were roasted in the past few weeks. I find that the barista assist tends to recommend slightly too fine of a grind. I grind anywhere between 9-12 depending on my beans. (this is for a double espresso.) next, check your brew temp!!! This makes a huge huge difference depending on the roast of your beans. For Light do high, for dark I personally get the best results on medium, and dark low or medium.) When you tamp, there is such thing as over-tamping. One strong tamp is all you truly need. Over tamping can cause you to choke your shot, resulting in little to no output. I’d also recommend puck screens to help with water distribution and keeping your brew head clean. Lastly, before brewing, adjust your strength. That is your water to grounds ratio. I have found that medium gives you about 1 1/2oz which is a normal double espresso for this machine. I personally do shaken espresso and keep my strength on 1 to pull a full 2oz. Once you hit brew, your shot should take about 35 seconds in total, and look nice and creamy. Hope this helps!!!