What exactly do you want:
1) that the transactions of your "unmined block" go through?
2) get the block reward with the "help" of a miner?
1) would be easy: like nc50lc wrote, you'll have to ensure the transaction fees are all above the current threshold to be mined. If you have 1 vMB (the number of transactions is not important, what's important is the weight) of transactions, then you'll in the last hours had to pay 0.02 to 0.08 BTC (
between 2 and 8 sat/vByte), because currently the fees are cheap.
2), which is what I guess you want to do, is something normally should be discouraged by the Bitcoin protocol, as it could allow an attack. But it's also interesting to discuss it:
Let's say you prepare the block. You include a transaction with a generous fee which is significantly more than what a miner currently can expect currently for a mined block. The coinbase transaction goes to you instead of the miner (I'm not 100% sure if this is possible, but otherwise you could agree with the miner about a transaction to you which shares the block reward). So you're "sharing" the coinbase reward with the miner.
But, regardless of how you do the math, it will never pay off for you. The transaction fee you'll have to pay will always be larger of what you'll receive as reward.
The only case I can imagine where there "could" be a profit for you, is if you find some friends who need transactions to be mined urgently and would then also be willing to pay a higher-than-normal fee. You would then bundle a group of high-fee transactions together and "offer" them privately to a miner. However, this has also a problem: you must trust the miner, as he could simply take the transactions and include them into his own block which doesn't give you the reward. (Of course, he can also do the same thing with the transaction with the generous fee you sent to him.)
So as far as I understand, if 2) is really what you want, it makes no sense at all.