According to 21.co a fee rate of 110 satoshis/byte is currently necessary for a transaction to be included in the next block.
How to configure electrum to use 110 satoshis/byte ? I know is in Tools > Preferences > Fees .. But I do not know what BTC value to put, i noob
1 byte is roughly 0.001KB. So just multiply that 110 by 1000 (it's actually 1024 but eh) and you'll get 110000 satoshi or 0.0011BTC/KB. Or 1.1 if you're using mBTC as base unit (check that from Preferences > Appearance > Base unit).
Also if you don't want to set it manually every now and then, you can use dynamic fee and use the slider to adjust the fee.