there are most probably bunch of tutorials online about bitcoin.
this will be just small description of possible setup.
1. mine on your own
maybe good if you hava A LOT of ASIC but if you do tomorrow somebody might buy more of the better ones
2. mine with bunch of others and share money
2.1 pick a group that is managed by somebody who you have to trust to pay properly
2.2 pick a group that is unmanaged that you can just join mine with others in p2p way
so if you pick path 2. -> 2.2 you have to:
1. download install bitcoin-qt the thing that will connect you to bitcoin network
it might take one day to download so do this first
2. download install p2pool the thing that will connect you to group from 2.2
(make sure you use python2 with pip for python2)
once you run it it will what config file to make so do that
3. download and install cpuminer if mining from cpu
4. once bitocoin-qt is in place and config is modified as instructed in p2pool tutorial restart bitcoin-qt in order to load that new config
5. start p2pool
6. start cpuminer with ./minerd -a sha256d -o 127.0.0.1:9332/ –userpass=yourbitcoinaddressthatyougetfrombitcoin-qt:anypassword
now what is going on is that you are mining bitcoin with decentralised pool of miners
this method can be applied to litecoin as well for which people do not make specialised hardware because of the algorithm it uses to make hashes.
old coins seem hard to mine so mining is like playing a lottery