Note that with a balance of less than 30 BTC2 your staking efficiency would already be close enough to 100%. If you have a higher balance, consider doing the following steps:

To achieve 100% staking efficiency:

1) Make sure you're allowing incoming connections and that you are connected to a lot of peers.
There's currently 25 nodes connected to the Bitcoin 2 network. If you see only a few peers connected, then have a look at the following to get better results:

Most home routers have NAT that by default blocks incoming connections initiated by someone else than you so you are likely connected to very few peers because of that and thus more likely to mint orphaned blocks. You can usually fix that and start allowing incoming connections with one of two ways:

... A) Launch Bitcoin 2 Core, go to Settings - Options. Go to Network. Enable: "Map port using UPnP". Then restart the app. You may also want to read this article: https://dirkmittler.homeip.net/blog/archives/3340
... B) Or follow the guide at: https://bitcoin.org/en/full-node#enabling-connections - the steps are exactly the same for Bitcoin 2.

2) You wallet should have 100 UTXOs (unspent transaction outputs, AKA unspent incoming transactions) or more.  This is because every time you stake or send an amount, that amount cannot be staked or spent for 101 blocks, while it is maturing (being staked). You can see the number of UTXOs that you have in the Coin Control dialog. Doesn't matter how many addresses or wallets they are split into. One single address can hold these 100 UTXOs.
if your balance is lower than 500 BTC2, You can get a close enough result without that much effort by splitting your balance into stacks of 5 - 50 BTC2. For example 150 BTC2 can just be split into 5 pieces and you'd be unlikely to notice the difference in efficiency of that versus splitting it in 100 parts. You can do the splitting by sending BTC2 to yourself.