I don't have HG. Am only sick once a day (usually evening), so generally keeping stuff down, but feeling rubbish all the time (worse in evenings). For me food helps. Even things that don't seem appetising can go down OK, though I can't bear the thought of meat or anything oily.
For me the key thing seems to be to eat at least every hour early and late in the day, and every 1h30 in the middle. Porridge seems to have good staying power. Toast works but lasts less long. Sweetcorn is good. Pasta is good if you have the energy to eat it. Small portions often. I have boiled a massive pan of potatoes and a potato piece from the fridge with a bit of brown sauce is good. The only problem is I am very loose, which I guess is all the fibre. I should be the size of a house given the amount I'm eating, but actually I lost half a stone when first sick and have now been flat for two weeks since learning to manage it a bit, despite eating all the time.
Sleep is also good. I am getting 9 or 10 hours a day if I can, and definitely feel more sick if I only get 7 or 8.
I read something a couple of days ago saying lack of protein can make sickness worse, so have also hard boiled some eggs and had some chicken last night, but too early to tell if its making any difference. I have some kidney beans to try too. I'd like to manage more greens, but salads have tended not to settle, and cooked veg seem too smelly. Have managed sweetcorn and peas, so will try to do more of those.
For me ginger biscuits are fine but just food, doesn't seem to help particularly. Mint isn't helping, actually it's one of the smells I've become very averse to (either everything in my house has become really smelly, or my sense of smell, particularly for human smells and tobacco, has gone off the chart sensitive). Blech. Wish I could go back to my old crappy sense of smell!