Two basic rules to my trading. Never risk more than 1% of my account in a trade and always trade with a stop loss. I also only trade when I have a technical opportunity to make at least 3:1 ROI. I don’t scalp.I'm not buying in the hope of a vaccine bounce, just pointing out that any good news on that front will destroy your position and your margin calls will be hideous - which is why I queried why you're going down that route rather than using Put options?
I've said it before, I like to buy and hold; its time in the markets that counts, not timing the market.
Initially, the stop is set at a technical and the lot size calculated so that my I am only risking 1%. Once the short trade triggers, the stop loss is moved to break even at the earliest technical opportunity and then moved a cycle behind the trade as it heads into deeper profit. Once the 3:1 ROI is protected by the stop loss, I can scale in, again risking only 1% at each scale-in. I can then start taking profit and buying stock with it.
With only 1% levered I’m unlikely to get a margin call. The biggest risk is the stop loss being bounced. That risk can be managed by only trading on high volume shares, which is why the index is attractive right now.
The FTSE is going sideways at the moment, looking for direction. There are many fundamental factors that will give it direction; a vaccine would probably give it a quick bulk exit. A slow ending of lockdown will probably give it a slow, grinding and volatile bull exit. A trade war with China, an extended lockdown which starts to take out big businesses or a second wave will all be bear signals and all will give a rapid fall.
It’s about being able to make money in a bear market.