Tips for following very low carb (keto) diets

The mental challenge

Keep it simple

Don't try to do everything at once. If you're starting keto, focus on starting keto. Don't try to also introduce fasting, or even worry about calorie deficit in the first couple of weeks. Get into ketosis, get well on the way to fully adapted, then start working on anything else you want to add.

Know why you're doing it

There are lots of reasons to try keto: glucose control, weight loss, mental gains, to name just a few. Know what your primary reason is, and measure success by whether you're achieving that. If your primary goal is to achieve great blood sugars, you're less likely to get upset if your weight loss is slow. It's also easier to push through any rough patches if you have a strong reason driving you.

Energy

Supplement electrolytes

When you read up on keto, you'll encounter the term 'keto flu': a collection of fun symptoms in the early days of keto. Supplementing electrolytes (sodium, potassium, and magnesium) can help with this. If you're on keto and feeling fatigue, the first thing to check is your electrolyte levels. Different sources recommend different amounts:

r/keto FAQ | Keto flu and electrolytes
Virta Health | ow much sodium, potassium and magnesium should I have on a ketogenic diet?

Personally, I found that trying to push up to very high levels of sodium and potassium was (a) really hard to do and (b) possibly a factor in some major water retention. I've opted for a gentler regime: a magnesium glycinate supplement as recommended (I was already doing this before keto), and less than 1000mg of supplemental potassium and sodium. This is something I'm still experimenting with, and will probably change. Experiment to find your own levels.

Bullet proof tea or coffee

Every morning as breakfast I have a mug of tea (~500ml) with ~15g of unsalted butter and 1 tbsp of MCT oil (see Carb Manager | MCT Oil For Keto and Beyond). This is definitely into the category of diet fad. There really isn't definitive proof that MCT oil is effective. But my personal experience is days where I do this I have more energy than days where I don't.

Walk

Even on days where I feel low energy, I find I feel better and get an energy boost if I get out and walk for a bit. Other gentle exercise would probably have similar impact.