Ethereum mainnet can be expensive to use, particularly during periods of high utilization leading to congestion. Note EIP-1559 below describes one of the reasons.
Cheapskates can often shave a few GWEI on fees, for non-essential transaction that can be slow, or for particularly small transactions. The process may not be worth your time, given the effort, but I feel particularly silly paying a $7 fee to simply execute some routine dApp smart contract or to send like 2 DAI.
In MetaMask wallet, when finishing approval of a transaction, click EDIT in Estimated gas fee, then Edit suggested gas fee. You can play with the Low, Medium, High selections, or enter GWEI [fee per byte] directly. Max priority fee [miner incentive] is typically fine at 1 - 1.5. But what should you pick for Max fee, where the large majority of your cost will be?
In https://ethgasstation.info, under the SAFE LOW label, check Gas Price (legacy). Say, it shows 20 for a calculated a guestimate workable for a routine low priority transaction. But is it high enough for your purposes, and can you go lower?
Scroll down below, to the Confirmation Time by Gas Price chart, and you'll notice that above a certain level, say 22, your wait time does not get shorter for higher GWEI. There is no point in going above that.
For even more fee details, scroll further to the Top 10 Miners table, Lowest gas price column, sorted in increasing order. Going below the smallest number [say 18]] pretty much assures that your transaction will not be mined at this junction. Going above the highest number [say it shows 23] is unlikely to give you a speed-up or a higher probability to get mined for some time. A number between those two, perhaps higher to the top [say 22], is typically doable, but may take 1 minute, or 10, or 100 to mine.
You may feel better knowing that your actual fee [Txn Fee] will be lower than the one quoted by the wallet, by 10-30%. One specs a high estimate for the smart contract gas needed, but gets charged for actual.
So, maybe you saved like 50 cents or a dollar on fees, or not. But you showed the wallet who's the boss, and perhaps also picked-up some blockchain lingo. And now you know for certain that crypto is generally voodoo, and Ethereum particularly so.
Ethereum fees situation got particularly unpleasant after instituting EIP-1559 earlier in the year, where instead of a fee market affected by the miners and producing peak utilization approaching 100% of the network capacity, now the network code itself forces utilization to 50% or less, by charging progressively higher fees and then burning them. Somehow related to the politics of the transition to PoS, this method effectively guarantees high fees most of the time, while shortchanging the miners. So much for the story popular during most of the Bitcoin history, that mining effort and cost are adding to the security of the blockchain.
In addition to ETH, Gitcoin allows donations via a zkSync service or using MATIC tokens on the Polygon network. zkSync uses rollups via Zero Knowledge proofs [Google away], which sounds cool, but a couple of times I’ve used it for Gitcoin donations, it was taking a long time, failing at times, and the fees were also non-negligible, given the initial sign-up cost.
Using the MATIC token from Polygon company is the cheapest Gitcoin option, but also requires more setup. Over a year ago, The company named Matic, an implementor of some variant of Plasma rollups, rebranded as Polygon, but the token is still called MATIC. Mostly used these days as a bridged L2, it has gained a bit of end user popularity, in a rather busy field of rollups and L2 networks, which now includes xDAI, Optimism, Arbitrum, and more.
Perhaps this success was due to semi-decent service reliability and tool usability, with fairy consistent transaction fees of under a cent, or simply superior marketing.
For this option, you’ll need to learn in MetaMask how to switch the network to Polygon, and also procure some MATIC token. Some of your colleagues may be able to help you out, and more instructions on getting MATIC are coming.