The main security consideration is the same with any platform, service, or exchange, to which you have to deposit your coins; mainly that you do not have custody of your coins for the duration that they are on said platform. With that in mind, you might prefer to split up 1 BTC in to a number of small deposits and withdraw all or some of each deposit before sending the next deposit, so you are never leaving more than, say, 0.2 BTC with ChipMixer at any time. Or you may decide that is more hassle than it is worth and just deposit the full 1 BTC in one go. Up to you.

There are some privacy considerations, though. Understandably, 8.192 BTC chips are withdraw far less often than, say, 0.002 BTC chips. If you were to deposit 8.192 BTC (or more), and then immediately withdraw a 8.192 BTC chip, then you weaken your privacy.

In addition to waiting some time between deposits and withdrawals, you can also split and merge deposits to aid with both the points I have made above. You could deposit 0.2 BTC, and then a few days later withdraw 0.128 BTC and leave 0.072 BTC with ChipMixer. Then, a few days after that, you deposit another 0.2 BTC, giving you 0.272 BTC, and allowing you to withdraw 0.256 BTC. By leaving some coins on ChipMixer and depositing and withdrawing from a pool over a period of days, weeks, or months, you maximize your privacy, and you can also make a number of small transactions rather than mixing your full stack at once.