The 42f8...e7c4 transaction has 2 outputs.
One output is 0.00049616 BTC to 1DAEpodRkJ2YitQYFKnBg5wnV4aYbARamj
The other output is 0.01475077 BTC to 1FHoe14m2FrGmvSuQyta1NKVEBFEQEL1wz
I assume one of those is the payment you were making, and that the other is the change being sent back into your wallet from the 0.01581193 BTC that were used to fund the transaction.
If the 0.00049616 BTC is your payment, then there is plenty of value left in the 0.01475077 BTC change output to do a CPFP.
If the 0.01475077 BTC is your payment, then you could use the 0.00049616 BTC in a CPFP transaction, but you would probably need to add additional funds to the transaction with a second input in order to have enough value to increase the fee significantly.
How do I use the change to do a CPFP?
Mycelium doesn't give me that option.
Is there a way to do it "manually"?
Maybe sending funds to the change address and double spending the same input?