I researched this a lot with DC2.
The travel bands aren't particularly effective (placebo, which is better than nothing).
Ginger has been shown to be more effective than a placebo in some studies (and as effective as vitamin B6 which is apparently one of the first things GPs will prescribe), but you have to have a certain amount (more than you could get from biscuits or tea). But, I found that that amount equivalent was in some of the pregnancy vitamins (Boots ones, IIRC).
I found that taking these vitamins (any vitamins) at night was better than taking them in the morning.
By far the best thing that I found was avoiding getting tired. Early nights, naps, and very gentle exertion was the way forward. Tiredness = nausea.
I suffered far less wtb DC2 than DC1. I wish I'd seen the GP with DC1 but didn't as I wasn't actually vomiting. But the nausea was crippling.
If nothing's working, please do go and ask for help (and then again and again because you'll likely be dismissed)